How did the factory attach the housing ends?

I believe the housing ends on an OEM 8 3/4 housing are formed into the tube that is created from flat stock. There are crimp marks where the tube is held while the forming happens.

This is how I think the housings are made.

1. Flat stock is rolled into a tube and welded down its length. (This can be seen inside the housing tubes)
2. One end is split front and back length wise a foot or so 90 deg from the weld.
3. That end is formed into the upper and lower half of the center.
4. This is repeated for the other side tube.
5. Another piece of flat stock is formed into a dish making the rear of the housing
6. The two tubes and the dish are welded together.
7. A ring is cutout and welded to the front side of the housing where the center section gets bolted up.
8. The mounting holes are punched into the ring.
9. The breather hole is punched and threaded.

Now for the ends, this is a guess but would be a way to make many housings that could then be made to the needed width for A B C E body cars.

1. The housing that is longer than needed is cut to a length specific to the car body.
2. The end is then heated and formed to the shape of the end flange.
3. It is machined and the holes punched
4. The spring perched are welded on.

Alternately the flat stock is cut to length before the tube is formed, and the ends are formed into the tubes before the two halves and the dish are welded together.
Finished housing.

I have two bare housings and both have the same crimp marks, weld lines, etc.

Crimp marks


Weld line outside


Weld line inside


1/2 tubes welded together