The backing plate adapters got made so quickly by laser cutting that I thought I would get the rest of it the brake parts done quickly.  I was wrong, because finding a good machine shop willing to do small jobs at a fair price is difficult.  Good, fast, cheap - pick any two!  Finally, I did get a local shop [good, almost fast, NOT CHEAP!] to mill out the centers of the Buick backing plates to fit over the axles and make some holes that a socket can fit through to allow the mounting bolts to go through to the adapters.  I got a professional welder to mate the adapters to the plates - he's NASA qualified, so I feel confident that nothing will come apart.  Here are the backing plates and adaptors before welding, showing how much metal had to be removed.  I did grind off the sharp corners to prevent bloodstains on my nice parts.

backing plates before welding

With just a little more grinding of the opening below the wheel cylinder, the backing plate assemblies slipped onto the rear axle.  Then I started mounting up the wheel cylinder to see how much I had to grind out of the top of the axle flange to get access to the hose fitting and bleeder screw.  A few minutes with a grinder gave me the clearance I need.  I got lucky with the positioning of the parking brake cable and didn't have to grind a slot for it.  See the lovely welds?  The plates were stitched every other inch or so plus three plug welds.  No warping!

rear backing plate mounted

  buick brakes assembledwelded link bar
Then I tried mounting the shoes, springs, and parking brake link.  The inside of the link bar interfered with the big bolt heads on the hex-shaped bearing housing, so I had to grind some big hunks out of the bar.  I made a reinforcing strip and welded it in at right angles to reinforce the link bar and still have clearance inside the drum.  Why parking brakes on a race car?  You never know when the hand brake will come in handy, and I will try to get the car licensed to run on the road at some point.

The shoes fit nicely around the axle, as did the other parts.  Remember, the Studebaker Indy cars took the 12-inch cable-operated brakes from the Dictator cars instead of the 15-inch brakes from the larger sedans.  Cables seem OK for parking brakes, but I prefer hydraulic action for the serious stuff.

OK, so now comes the part about mounting  the drums.  The big aluminum drum has a lip that engages the backing plate to keep water and dirt out.  The inside edge of the drum needs to be about 1/8th inch off the inside of backing plate, just flush with the rear surface of backing plate.  The hub then has to pick up the five holes for the studs in the drum (5 on 5-inch dia.).  The 1928 Commander axle was originally equipped with wood-spoked wheels and 15-inch brake drums.  While the Buick drums are close to the same wall thickness as the old Studebaker drums, the 1.5-inch thick spokes placed the flange on the hub fairly far out on the axle shaft.  It's going to take a lot of detailed measurements and re-checking to get the design just right before getting them machined.  The original parts were drop-forged steel that were then heat treated at 1550 °F for 15 minutes, then cooled in air.  The new ones will probably be machined from a billet of high strength steel, like 4140, and heat treated for toughness.

Here's the drum slipped over the shoes and a rendering of what I think the hub will look like.  As with the original Buick hub, the large flange will go inside the drum with studs pressed in or the flange holes will be tapped.  I still haven't figured out the part of how the splined center hub for the knock-off wire wheels will get incorporated.  It will either become part of the drum mounting hub or will be a separate part to be secured to the studs.  I need to confer with the wire wheel people about this.  The outer end of the hub has 2.75-inch diameter threads to screw on a cup-style wheel puller, but with one of the "modern" Studebaker wheel pullers using three arms, I might be able to do away with the threads.  The end of the hub will be covered by the wire wheels, anyway, so it won't show.   Now I just need to find the machine shop that can cut the 1-in-12 tapered hole in the hub- and then cut a 1/4-inch keyway into the taper.

1963 buick aluminum drumrear hub rendering  

Here are the front backing plates installed over the huge steering knuckle (3x7 inches).  Note the wheel cylinder will be behind the axle, so the backing plate needs to come off for bleeding.  New bearings will be installed.
Buick front backing plates
Here is the rear side showing the king pins and steering arm. 

Buick front backing plates - rear side

Now, there will be some folks out there that think these aluminum drums are a little over the top.  Indeed, they are, but I'm sure that drums intended for a 5000 lb Buick boat will do an adequate job on a 2500 lb Studebaker Indy car.  For the most part, they will be hidden behind the wire wheels, while giving me lots of peace of mind, even if I'm lapping at 100 mph in some vintage car event.  I heard a song from "South Pacific" the other day, with a line that went something like, "If you never have a dream, you can't ever have one come true."  I'm dreaming big time!