You can mount em facing to the rear, but then you can have hose routing issues. If you mount em to the front then disc brake 73-76 A body brake hoses fit like they are supposed to.
FMJ calipers are a great upgrade too. The A body caliper pistons are 2.60". M body, not sure about F or J, but M body uses 2.75" pistons in their calipers thats made of phenolic plastic. I was able to buy plated steel replacement pistons made by allied signal on closeout from rockauto to reload my M body calipers
This is a screaming deal for the price guys. If i didnt have all my parts for both cars, i woulda jumped on this great deal. Not trying to steal your ssle thread, Just wanted to give another heads up on why the M body calipers make a good upgrade.