It's pretty much a stock 6A MPU, with a few seemingly minor modifications.
This is a known mod for a single firepower ROM, but I don't think that's in place here:
There are some changes where you indicated an additional resistor, but I'm not sure what the significance of that modification is. There's a missing jumper below the CPU chip and there is a missing RAM chip (both of these changes are so a 6802 CPU can be installed). I think that's about it.