adding os 9 after os X?

[Michael McPherson]

So I got my cube recently off of ebay and I upgraded
the ram and hard drive.  There were no system disks
with my cube, so I bought OS X (Jaguar) at the apple
store (literally 1 block down from my folks house...sweet).

I've been running os X happily, but I tried downloading
an os 9 based proggie the other night and I was rather
disappointed to learn that os X classic mode still
requires os 9 to run older apps.  For some reason
I just assumed that classic support was built in :(

So my question is this...if I can get a cheap copy of
9.2 off of ebay or something...can I install it on my system
so that os X can use it?  or will I need to format my drive,
install 9.2 then install X?

The other option is to just avoid running non os X apps, but
it would be kinda nice to have the os 9 functionality if I can get it. 
:)