There are 2 different styles of rear radius rods for 1932. Both styles bolt to the bottom of the axle housings. The early style (B)have a bend at the connection to match up to the mount on the axle housing. The late (18) style are straight and the mount is angled on the axle housing.
Years ago, I had to drive to work on a wooded rural road. I would see deer almost every morning in Spring and Fall. I hit a couple of them. I added a deer whistle to my repaired car and never saw another deer on that road. (Just my experience)
You can do a simple Pass/Fail test just using the heads. Just install some heads so that are known to be good and block off all the water openings. Fill the block with water and pressurize. If the assembly will hold pressure, you are good to go. If it does not, it may be difficult to...
The other alternative would be to use the '35 drums that you have but add a spacer ring to them to allow the use of the '48 wheels. These spacer rings used to be available many years ago when people wanted to use later wheels on their mechanical brake Fords. I doubt that they are still...
If it is an F100 steering box, the easiest way to fix the situation is to change the drag link so there is some way to adjust the length. This will require having a threaded tie rod end on at least one end of the drag link.
Hot Rod Magazine did a test on a number of different manifolds a few years ago. They showed the Slingshot to give better performance than the Thickstun PM-7 / Tattersfield. (Your mileage may vary.)