After some good advice from Tankmodeler, I found a cheap M3 kit at a local hobby store. It has much more accurate running gear.
HOWEVER, please don't use the track or road wheels. The road wheels have 6 spokes instead of the correct 5 and the track has the end connectors in the middle of the pads instead of joining two pads together. Dip into the spares box for proper spoked early Lee/Sherman road wheels for this.
The rear idler mounts are complete rubbish as well and the kit doesn't have the proper "pepperpot" exhausts or rear engine plate of the M2.
If (and only if) you are up to spending a bit more, I would suggest either buying the Academy M3 Lee or the new Takom or Minicraft early Lees. The Academy kit is pretty reasonably priced now that the much better Takom and Minicraft kits are available and has better detailed bogies, good idler mounts, the proper spoked wheels and quite reasonable track. The other two kits are much better again, but are much more expensive if all you're doing is using the running gear.
Minicraft also has a new kit of the earlt R-975 with the pepperpot exhausts as a separate kit that you could use down in the hull (as it's a clear view down into the engine bay in these tanks).
The 37mm M5 gun and mount are going to need to be scratchbuilt, but you may be able to get Commanders Series models to sell you just those parts as they have an M2A4 Light Tank kit and I think that's the only other kit and vehicle that has that gun mount.
I'm sure that more unsolicited advice was
just what you were looking for at this point, right?
Paul
Paul