Thanks to Robcfg for telling me about Fiji for stitching! I had tried a bunch of other tools with little luck, but Fiji is easy to use and fast.
I've been trying to get another 1977 Electronic Battleship to get another MP3208 to decap since I damaged the last one. I finally picked one up, but it turns out it is different from all the others I've seen- this one has a TMS1000 labeled MP3201 CSP 7736, a 555, a 4016 and an LM324, along with a bunch of transistors, caps and resistors.