M3A1 Stuart welded hulls and production numbers

[mshackleton]

I'm trying to get to the bottom of when welded hulls were introduced on M3A1s and, more to the point, when the normal Stuart angular rear hulls were replaced by curved rear hulls. Hunnicutt barely mentions welded hulls at all and there is no mention of curved rear ends. Other books only mention them in passing.

Also, I've never seen anything published about M3/M3A1 serial/registration numbers and how they related to the host of changes made during Stuart production. Can anyone help?

I'd also be interested to learn about M1/M2 Combat Car and M1/M2 family Light Tank numbers.

Cheers
Mike Shackleton