I bought the Asuka-Tasca Sherman M4A1 Direct Vision Kit 35-025 in (2015). Unlike in earlier versions of this kit, sprue E, which has most of the parts for the lower hull assembly, has a lower hull back part E4 instead of a lower hull back part E3. Also, in the instructions, only part E3 is shown. What I am calling the lower hull back is the part on which the rear doors for the hull will eventually be mounted.

E4 has a straight upper edge, so there is a significant gap between is upper edge and the curved lower surface of the cast upper hull.

Asuka's M4 kit includes part E4 on sprue E:

http://www.1999.co.jp/eng/image/10337291n3/40/3/1

In contrast, part E3 includes a curved portion that is contoured to the curve of the lower surface of the cast hull:

http://www.1999.co.jp/eng/image/10169848n4/40/4

Also, from my research, although the instructions to the kit only show the three part transmission cover, it appears that the M4A1 tanks that had the part E4 type lower hull back always had the single part transmission cover.

So, my question is: can anyone who knows more about Sherman's than I do confirm that when the back lower hull for a M4A1 looked like E4, the transmission cover usually was a one piece cover and not a three piece cover?

Fortunately, the 2015 version of Kit 35-025 does include the one piece transmission cover sprue and I have found directions for other kits that show how to mount the one piece transmission cover on the front of the tank. Also, it appears that one of the four tanks whose decals are included with the kit may have had this configuration.

So if I can get the above question answered, I should be good to go with proceeding to finish assembling the hull.