I helped a friend remove and reinstall the factory starter without jacking up the engine block. We disconnected the starter wiring harness at the junction block (horn relay) then removed the exhaust manifold bolts. I crawled under the car and removed the starter bolts. Now the fun part, while he held and manipulated the exhaust manifold, I was under the car doing the same dance with the starter. It took awhile to get the starter out but we did it. It was much more difficult to put the starter back in as gravity was not helping with the installation. Yes, it was a struggle, those starters are heavy! The down side to doing it this way, scratches on the frame and starter when wrestlering with the manifold and the starter. Wonder how the factory did this in 1965? Good luck.
John