A745 3peed to a A833 swap

Speaking from my own experience in converting my 68 cuda from auto to manual A833, the hump is not difficult to line up over the tunnel. It basically only fits correctly one way. Trace around the outer edge of the hump when in place on the tunnel and cut inside that line about 1 inch to leave sufficient metal to weld it to. You can also rivet it in place, I suppose. Once I had the hump welded in, I then bent the excess tunnel/floor sheet metal up from underthe car to fit around the contours of the hump and sealed it all up with seam sealer.

Most of the 4 speed humps on the market require some additional fabrication at the lower rear section due to the fact they are made to fit later (70s) A bodies as well. If you get one of these its just a matter of cutting a small section of sheet metal to fill in the gap and either welding or rivetting it in place.

I cant speak for clutches as Im still considering which clutch to buy.

good luck.