I need some help. I bougt a Fiberglass 32 last fall. It has disk brakes all around with A Ford 8" rear end but Chevy engine.

How do I know what year/make the disk brakes are from? Chevy or Ford and about what years???? They are the smaller stock/standard type, not performance aftermarket. The rear is lugged with 4.5 lugs with 1/2 inch threads. The front is 4.5 lugs with 7/16 threads. Not sure if that matters.....

The casting numbers on my rear calipers are "0709" in small numbers then then "5" and "388" in large numbers.