After using my fuel pressure gauge I have gas bubbling out of my shradder valve. I'm assuming I need a new valve core.. Is there anything special about this valve core or would one for a tire valve stem work? They look almost the same to me, does anyone know? If not where can I get the correct one? Anyone know a part number?

I would try and find one rated for use with fuel at least. The ethanol in modern gas will eat normal rubber.

as far as fit goes, they are the same as most tire valves.
but the seal in one for fuel is completely different.
you should be able to pick the right one up at your local GM dealer.

or pick up one at the junkyard. Most Schrader valves are the some from any late 80's GM car...