mounting an atx board in a case from 1997

its a gateway destination case; I want to mount either an atx or a micro atx motherboard into it. any ideas if this will just fit right up(the current mobo is a P2 mobo; I know nothing more about it).

or if I need to fabricate new mounting points, in which case does anyone have a 1:1 scale printable website file or whatever that I could put in there to see if a full atx will fit?

If I recall correctly, Gateway used ATX back then, so it should be the same mounting points. It depends a bit though, on if they were using the slimmer ATX form factor mounting and didn't include the Full ATX board mounting holes.

if you can open it up and take a picture, it should be easy to tell.