I have a Sherman IIa (M4A1 76) mocked-up--Tamiya M4A1 lower hull, Faxon upper, Bandai T23 turret...Near as I can find out, the M4A1 76 was 9" taller than a conventional M4, but sitting alongside Tamiya's Firefly 1c it sure looks much taller. Any thoughts on this?

This may be a pretty basic question, but did you sand off the required thickness from the bottom of the Faxon hull? The hull is actually sitting on a large resin 'foot' a couple of mm's thick which needs to be removed.

Your height may be correct depending on how you measured it. The T23 turret was 2 inches taller then the 75mm gun turret. The vision cupola added another 7 inches for a total of 9 inches. Fresh T49 rubber chevron track added another 2 inches when compared to T51 mono block and T54 steel chevron.

If you measured from ground to top of vision cupola you should be 9 inches taller on the M4A1 T23, 76mm gun tank. If you measured to the top of the turret roof then your off by 7 scale inches.

M4/M4A1/M4A2/M4A3/M4A4 75mm gun height to top of split ring commanders hatch - 108 inches

M4A2/M4A3 75mm gun M4/M4A3 105mm gun height to top of split ring commanders hatch - 108 inches. Height with vision cupola - 115 inches.

M4A1/M4A2/M4A3 76.mm gun height to top of vision cupola - 117 inches.

Correction - I should have said 'T48 rubber chevron' instead of 'T49 rubber chevron'