I uploaded the Entex Baseball (1) ROM array with the top metal layer removed. I checked the bits and I didn't find any differences.
I also got the Speak and Read and the black Entex Space Invader with the TI chip. I'll measure the clocks before I decap it. As well as the case and MCU, the overlay is different from the gray one. Makes me wonder what happened that they couldn't use anything from the original run.