I'm uploading pictures now, http://rides.webshots.com/album/582194854SNgLnW

I expect they will fit in a 17" wheel but it'll be close and is worth checking. It's only 1/2" clearance on the 19.5" NAPCO wheels I have, see the pictures.
You may find a smaller diameter rotor with the same other dimensions, I didn't look because I wanted as large a disc as I could fit.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
---All pictures---
"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-