Was there an even larger stone circle at Lough Gur?

Mythical Ireland recently had a post about Ireland's "Stonehenge", a very impressive site that was destroyed in Co. Louth in the townland of Carnbeg. It got me thinking again about the missing stone circle at Lough Gur in Co. Limerick and I had another look at some of the the evidence for it. I had initially thought it was just north of Grange B (the large circle that most people would be familiar with at Lough Gur) from an old 1840s Ordnance Survey Map. (See below)

Grange D stone circle to the North of Grange B stone circle (still intact) © NMS

However from chatting to Tim Fitzgerald a number of years ago (the owner of the land on which Grange B is located) he indicated that there was a large crop mark in a field to the north-west of the circle (across the road). This is marked in the SMR as an embanked enclosure and you can see from some of the aerial photographs attached that it stands out pretty clearly.

Highlighted embanked circle © NMS

Highlighted embanked circle © Microsoft

In "On Certain Megalithic Remains Immediately Surrounding Lough Gur, County Limerick by Bertram C. A. Windle 1912 / 1913" - Windle goes into some detail about this missing circle known as Grange D. In the survey there is some confusion between whether the missing circle was to the north west or north of Grange C (and whether it was on the same side of the road or across the road from it). Are there in fact two large missing circles?

In the above Windle states "Professor Harkness says (p. 389): "A short distance northwards from this fine circle [i.e. circle ' B '] the remains of another are seen. This second one is entirely composed of blocks of stone. An old road runs through the western side of this second circle; the portions which remain are, however, sufficient to afford a knowledge of its original size. Its diameter is larger than the fine stone and earth circle at Grange Cottage, being 170 feet." Mr. Lynch says (p. 300): "About 30 yards north of the chief circle there is another circle with a diameter of 170 feet. It has no rath, and only six pillar stones are left. In Fitzgerald's time there were seventy-two stones in this circle, but about sixty-five years ago it was destroyed by Mr. Edward Croker, of Grange'. Finally Mr. Lewis (p. 524), who mentions the same facts as have just been alluded to, seems to have missed the remains which still exist, for he says : "It is said to have possessed seventy-two stones in 1826, but only sixty in 1828, and of these all but six were destroyed in 1830; if any of those six are left now, they are probably built into some of the stone fences, for I did not see them."

Windle goes on to say that there may be an issue with fitting Grange D beside Grange B. "From the segment which remains, Professor Alexander has been able to compute the diameter which the entire circle, if it were a circle, possessed, and this would have been 225 feet. Now, if a circle of this diameter were to be described on the plan, it would intersect circle C. Either, then, this was no part of a circle, or the stones have been so much disturbed as to make it impossible to draw any deductions respecting them."
So it seems that there were some stones remaining in 1830 and by tracing these (if they were a circle) they would run through Circle C (which still exists today). However I’ve tried this on google maps and if you take the diameter of the circle as being 170ft (as per Lynch above) it actually shows that the old 1840s OS map is to scale and a circle (with its western edge missing) would fit between Circle C and the field boundary.
Grange Circle D fitting between Circle C and boundary / old road if 175ft diameter © Google
Professor Alexander gives a diameter of 225ft based on remains when he inspected. However again using google maps I think a circle of this size could have fitted beside Circle C (see the mock up below). 
Grange Circle D fitting between Circle C and running through boundary / old road if 225ft diameter © Google
What is missing though is any crop mark for the circle. However as it states above it was “entirely composed of blocks of stone”, so I’m guessing that a stone only circle (without a bank) would have left a much fainter crop circle than an embanked circle? 

So the question remains, would it have been possible for a circle of 170ft diameter and between 72 and 60 stones to have existed to the north of Circle C? For comparison purposes Grange B is approx 153ft in diameter. From the google maps evidence it appears that yes it could have.
Mock up of possible Grange D stone circle beside Grange C
Another option is that the missing Circle existed 'across the road' where the crop marks exist today. There are some stones in this field and in Windle's survey they are described as an "Avenue". How they would relate to a potential stone circle I'm not sure - I've included a picture of some the stones from the avenue and the area of the field where the crop circle is (see below). This circle looks to be more of an oval rather than a circle and from google maps measures 326ft at its longer width and 243ft at its narrower width.
Some of the stones of the "Avenue" and the area of the field where the embanked stone circle would be.
In Windle he says of the Avenue “Harkness thought that they might have formed the western side of circle D but this is clearly impossible. Mr. Lynch thinks that it was the avenue leading to a completely destroyed circle in the same field. Harkness (p. 390), in his description, alludes to "a large cup-shaped depression about 210 paces in diameter ; but whether this is a natural or an artificial production there is not sufficient evidence at present to determine." Mr. Lynch also alludes (p. 300) to this depression, which he says has a diameter of 230 feet. He adds: "Not a stone is now left of this circle, the last having been taken away about sixty years ago. There are traces of this circle having been formerly surrounded by a rath." There certainly is a cup-shaped depression in the field ; but I think it better to agree with Professor Harkness that there is not sufficient evidence to say what it may have been, or indeed to decide upon its natural or artificial origin.”

Mock-up of what the embanked stone circle "might" have looked like - a lot of speculation here on my part!

So to conclude is the existing Grange B only the “baby” of two much larger monuments? Namely a 72 upright stone circle without a bank with a diameter of probably 170ft called Grange D and an unnamed embanked oval of 326ft? More detailed surveying of the area at Grange D would certainly go a long way to help figuring it out. 

Thanks to Microsoft & National Monuments of Ireland for use of their aerial photographs respectively.