Some speculation on a 74+ big bearing 5x4.5 rotor

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   This might be a giant waste of a few hours but here goes...
I've been reading up on past threads brake rotor upgrades and the issue with the 5 on 5 lug pattern for the 12 inch rotor that is a bolt on. Would be nice to have a 12 inch with 5 on 4.5 because reasons.

Having some time to kill I did some Rock Auto catalog mining. If you click on the part numbers in a list on Rock Auto it gives you the other applications that use the same part. Clicking on the rotor part numbers was no help, how about the bearings?

Our '74+ big bearing spindles use WJB WTA12 for the outer and WJB WTA18 for the inner, to pick the first manufacturer in the list.

Click on "WTA12" and you get... nuts! "Results may be incomplete due to size of result set" looks like everyone and their sister used this bearing. Dead end for now.

Click on "WTA18" and you get some more useful results. All our familiar 70's Ford mid and full size. Some truck applications that probably aren't 5 lug. Lots of Mopar. Start at the top: Chrysler Imperial '74-'75.

Looking up a 74 Imperial rotor gets you this little guy:

https://www.rockauto.com/en/moreinfo.php?pk=391221&cc=1063640&jsn=3514

RAYBESTOS 7034R $35

Rotor Diameter, Outer (IN) 11.750
Rotor Thickness, Discard (IN) 1.180
Rotor Thickness, Nominal (IN) 1.245
Rotor Type Conventional
Height, Overall (IN) 4.984
Surface Finish Plain
Wheel Bolt Circle Diameter (IN) 4.500
Wheel Bolt Hole Diameter, Maximum (IN) 0.548
Wheel Bolt Hole Diameter, Minimum (IN) 0.540
Wheel Bolt Holes, Primary 5

5 on 4.5 and 11 3/4 inches - our "12 inch" is 6040R is 11 13/16 so pretty close on the diameter. Overall height is bigger, 4.984 - 4.829 = 0.155, less that a quarter, more than an eighth.  0.06 inch of that is in the thickness of the rotor. No dimension for the hub diameter which sucks. None of the other manufacturers list it either that I could find.

Checking the bearings, inner is WTA 18 of course, that's how we got here. Outer is WTA 16. The Centric listing has a nice picture with dimensions. 410.91012 is for our 74 up application, 410.91018 is the Chrysler, and bingo, the inner diameter of the inner race which the spindle goes into is the same:

So it would fit on our spindle with the Chrysler bearings.

Would it work? Can't tell without better drawings. Or parts in hand. Maybe you guys already know the rotor thickness kills it - don't have enough experience with these cars to say. I checked u-pull yards local to me and none of the Chrysler products were in. I did pick up the Continental/Mark caliper brackets though.

Worth popping 35 bucks to do an experiment?