I have looked at the 6800 in the past but never used it. I know it is very, very similar to the 6502, and I was just looking back at my
address-decoding page in the 6502 primer to see if there would be something to help you, but I guess now I have to ask for more specifics. What parts seem the most mysterious?
I'm wondering about your RAM and ROM sizes too. I assume you mean 64
Kx8 (like a 27c512) ROMs and 32
Kx8 RAM (like a 62256); but the 6800 has a memory map of 64KB, so you cannot get 160KB of memory, plus I/O in that space, unless you do some sort of banking arrangement with external hardware. A beginner definitely won't be using that much memory anyway.