You'll have a first 1MB chip thanks to the onboard 512KB + trapdoor A501 + mod, the second 1MB chip comes from the DKB.
FWIW I had a 2mb upgrade, but not the DKB one and it came with 2mb in total. You could have memory at c00000 as well, I think I had about 1.8mb in there.
The connection to gary was a bit of a nightmare, it came with clips to attach to the legs of the chips but I ended up putting in another story in the gary tower. I can't remember if that was because the order of them was important (the 1.8mb board came with a complex board that sit between gary and the motherboard.
Unfortunately I stripped it all out, so I'll need to find all the parts and try to make it work again. I'm not sure all the parts work though, even my a500 was toast the last time I tried.
