The 71 Datsun came back in for a 5-speed swap. He bought a rebuilt short shaft 5-speed from a company that said it was a direct bolt in. So it went from an estimated 3-4 hour job, to about 30 hours. It was no where near bolt in. The bellhousing was too large to fit in the transmission tunnel, so it had to be cut out. I had to widen it about 2 inches at the bottom, and I had to raise it over 3 inches. The frame and the bellhousing had to be clearanced. The exhaust had to be rebuilt starting at the collector, because the stock exhaust did not clear the bell housing. The transmission mount was miles off, and the stock rubber pad would not even bolt to the transmission without modification, so a new one was made. And his stock drive line had a fixed 4-bolt flange, and the new one has a slip yoke, so it needed modifying as well. And I ended up having to make a new clutch push rod that was about an inch longer in order to engage the clutch.
Heres the tunnel and frame cut from the bottom, huge hole.
New transmission mount.
And heres the new transmission tunnel, still wet with seam sealer.
You can also see that I welded Jerome's shifter from the 4-speed onto the new 5-speed shifter.