So, overall the parts are crisply cast and detail appears quite decent. Then I compared the kit to the drawings in the AJ Press book and some cursing ensued. . .
The upper hull certainly doesn't match the drawings. So I anticipated that awful AMS situation of do I try and fix it or do I just live with it? Then I decided to compare the kit to the photos I took of the St Chamond at Saumur this spring. And they seemed to match the kit rather well. What it seems like (and I am kicking myself for not taking some quick measurements while I was there) is that the drawings do not match the preserved vehicle especially well and the kit lines up under early inspection fairly well. Phew! And a good reminder that just because there are drawings out there, it does not mean that they are correct.
So, working on the upper hull things began smoothly except for two niggling issues.

There are six small strips to represent the angle irons on top and five of them fit perfectly. The sixth, outlined in blue, simply did not fit. The slot the piece fits into was simply too narrow to allow the piece to fit. i farted around trying to trim it larger, said to heck with it, and cut the piece to fit over the slot. Tamiya extra thin cement was my friend. . .
In addition, the piece over the engine (outlined in red) should stand taller than it actually does, at least using the Saumur example as a guide. It looked close enough to me, so away I went.