Honda engine fitment Q, ATC 90 frame

[bigcrunch]

I found a honda TRX 125 in a junk jard, with the horizontal engine all there.
Will it mount in a ATC\US 90 fame? with modifications?

[motoman1012002]

you'll have to make a battery box the rear of the motor by the high and low gear box i think is a little wider too

[bigcrunch]

I'll probably only use the hand pull to start, as I do on my 2 others now :)
I don't want to modify a frame if I go vintage route, if I can find a Nicholson or similar may do that path. Anyone do this before?