OK, so I never really liked the generic repro full-moon flippers on my '41, and started looking for some more interesting caps. First problem - it runs Vintique Gennie wheels, and the availability of caps to fit is slim. And from research, the chances of a cap actually fitting seems fairly slim too. So I've looked at everything. Caddy sombreros, '52 Buick, '53 Stude, '50 L:incoln, '50 Olds, etc etc. All look good, but not readily available for trial fitting, and I didn't want to make a series of expensive mistakes. Also, I wanted 2-piece covers, but not the cap/ring look that leaves an expanse of wheel between the cap and the ring... I did find a set of '52 Buick full covers, bought them, and - boom. Way too deep-dished. Fail. Yet more wall art. I didn't want to go the same route with expensive sombreros, so I kept looking. And in the end...here's what I found and what I did. First, in a local old-parts store, I found some dog-dish Caddy caps. I think they're '40? They're simple, and have a brass emblem. I also found a pair of full-width beauty rings. I have no idea what they're from, but I want to say '48 Chrysler. Anyway, the tangs on the rings looked like they'd grip to the Gennie rim, and the center hole was almost the same size as the inner fitting ring on the cap. I took the plunge. In the pic below, I'd already cleaned them up a bit. From the backside, you should be able to see the cap's 'fitting ring'. Of course, it didn't fit inside the Gennie mount. I didn't think it would. So, to make the cap fit, it'd have to be mounted to the beauty ring. But the hole in the beauty ring is too small. So... let's center the cap, fix it in place (duck tape worked) and mark the ring (all on the backside of course). Now let's cut. I marked up a pair of snips with a sharpie for reference, and went round the whole ring, snipping away to make a bunch of small tabs - each about 3/8" wide. 10 minutes later... Next thing was to bend them inwards (towards the back side of the rim) to create a 'bowl' for the hubcap to sit inside... In the picture below, you can see that I've not only bent them in, I've also started fixing them to the cap. This is a simple process - drill a hole in the tab, follow it in to the cap, and insert a sheetmetal screw. Put as many screws in as you like. I ended up with 8 or 10. I didn't count. It's important here to make sure that nothing moves when you add the first few screws, because you need the cap centered on the ring. The next thing to do is test-fit on the rim. And the next thing to do is find out that the Gennie wheel is very shallow indeed, and the fitting ring on the cap fouls the mounting ring on the wheel. So, out with the grinder, and trim about 3/4" off the cap ring (below) Then fit them again. And ta-da!! homemade '40s Caddy caps that fit a modern Gennie wheel, and for less than $60 the pair. I know I've got to: Get my bias ply tires, Paint the rim, and detail and polish the caps, but that's a big headache off the list.