Inf adaptation to ppd

I have an old (expensive) printer (no drivers for win 7) that is a postscript printer. I have a ppd file for it
and two inf files for other windows os (2000, xp). The printer is networked off a 32 bit xp win server.
The win 7 box(es) can't install the xp drivers because they are 32 bit. BUT. This is a postscript
printer and the postscript driver software (dll's ?) in win 7 should work ok IF I can get the
existing inf files adjusted to point to the ppd that I have. These are both text files and
therefore the 32 bit vs 64 bit issues should not be a problem. How do I hack the inf files so that they
a) refer to the ppd file I have and b) match the OS (win 7) I need to use them on?

I realize this may be a naive question, so what am I missing? Where would there be a 32/64 bit problem if
there is one?