Technical Olds/Pontiac brake swap

I'm narrowing a '60 Olds rear end for my '28 high boy. The Olds rear end came to me with no brake shoes or hardware, no drums, just backing plates. I have what appears to be a complete rear brake set up from '57-58 Pontiac (left over from when I put Wilwood discs on the rear of my Willys PU). The Pontiac backing plates are more compact and a little prettier than the Olds version.
Olds housings have a full round flange while the Pontiac backing plates require a flat across the top. The axle offset (housing surface to drum mounting surface) seems to be compatible. Anyone see any reason why I can't just grind the proper flat across the top of the housing ends and bolt 'em up?

 

should work just fine .

 

I thought so too but before grinding on the housing I thought I'd like a second set of eyes or some experience to weigh in. Thanks.

 

I ground my 57 housing to use 62 brakes, worked fine.

 

Great, thanks Kev. I'm making some collars for my narrowing jig to fit in the Olds carrier bearing saddles. I hope to have the housing cut and back together this weekend. The new radius rod brackets, quarter elliptic springs and brackets are done. Looking forward to getting it back on all fours soon.