Series 70 1911 and Crimson Trace Light

[benos]

A friend asked me this:

As you know I have a series 70 colt 1911.

I recently purchased a "lightguard" from Crimson trace that was claimed to fit Kimber and Smith & Wesson 1911 full size, Compact and Bobtail frames.  CT has told me that it doesn't fit my gun.  The local Gun Store though it would as did I.

It does not fit my Colt and it appears to me that my Colt trigger guard is a bit too "fat" to be a fit with the guard mounted light housing.

My question to you, is, do you know what the difference in guard dimensions might be or where I might find that info?

It would appear to me that a small amount of carving of the plastic would make this fit workable.  Too simple?

I would also be able to machine the trigger guard in my mill if I had some dimensions to go by.  Trial and error sucks...especially the error.

It seems ludicrous that as many real Colt 45s that have been produced that CT has no product to fit them.

It also looks like a market vacuum that needs filling.

Any productive thoughts would be appreciated.