Bolt in transmission crossmember
 

Did some research but cant seem to find a definite answer. So looking online ive come across a few different crossmembers for the 68-72 A bodys. Some of them look like they bolt directly to the frame and others sit in rubber insulation. I know that the gto's had the rubber insulation on both ends of the crossmember. So where do the bolt in styles come from? Is that for the convertible frames or was it a buick or chevy thing? Also is it possible to use the direct bolt in ones in my 69 to get ride of the rubber insulators?

Yes the bolt in ones will work. A chevelle cross member would be a good solution if you have one available.

I simply removed the rubber isolators on dad's 69 GTO and bolted it to the frame. His happened to be just long enough to reach. Did that maybe 25 years ago when he started racing the car regularly. Shimmed the trans for proper angle and has been fine ever since.