I did find my code at C000 but only after I concatenated gs04 and gs05 separately from gs03. Keeping the main code separated from the paged code.
Ah ha! I can move on now.
I do have a question with:
extern WRITE8_HANDLER(gunsmoke_c804w);
This is obviously an external device and not an actual memory location. Possibly a demultiplexer (74138) that enables the correct banks and addresses on the eproms.
Is the c804 designation meaningful to what device on the board we are talking about here?