The first order of business was the mounts. I've done several swaps, but this is the first time that I had a SBC and a Gen 3 motor sitting side by side. So, armed with my trusty tape measure I came up with adapter plates for the stock towers and mounts to place the motor just where I wanted it. I made these mounts out of 3/8 plate. There pretty much run of the mill plates, except that the SBC mount holes are 1/4" below the Gen 3 mounting holes. This will raise the motor by about 1/4".
Here are the plates in the middle of painting:
I also needed to modify the passenger's side tower. First, I removed the top of the tower:
Then a duplicate of the mount "top" in flat steel:
Welded together and a rough pass with the flap wheel:
Gusseted under the edges to add back some strength and blasted:
All done, in paint: