Disc brake education

[MoparCarGuy]

Yes, the 11.75 rotors fit inside 15" Rallye wheels. The sliding calipers work just fine so go with what you can source. The combination valve and metering valve setup https://www.amazon.com/gp/product/B07TPCCT57/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1 used after 1/1/1970 should be installed with the proper booster and master cylinder. You will need a brake line adapter to connect the combo valve to the metering valve. This is the line needed. https://www.autozone.com/brakes-and-traction-control/brake-line/p/ags-3-16in-x-8in-3-8-24-inverted-7-16-24-inverted-pvf-steel-brake-line-adapter/561006_0_0?searchText=PAA-R340

If you have a long duration cam and low engine vacuum, you may also need to consider an electric vacuum pump to make the 18-20" of vacuum needed for the booster.

[340Challman]

Yes, the 11.75 rotors fit inside 15" Rallye wheels. The sliding calipers work just fine so go with what you can source. The combination valve and metering valve setup https://www.amazon.com/gp/product/B07TPCCT57/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1 used after 1/1/1970 should be installed with the proper booster and master cylinder. You will need a brake line adapter to connect the combo valve to the metering valve. This is the line needed. https://www.autozone.com/brakes-and-traction-control/brake-line/p/ags-3-16in-x-8in-3-8-24-inverted-7-16-24-inverted-pvf-steel-brake-line-adapter/561006_0_0?searchText=PAA-R340

If you have a long duration cam and low engine vacuum, you may also need to consider an electric vacuum pump to make the 18-20" of vacuum needed for the booster.

Was planning to stick with the manual brakes. I like them and can lock them up as is with no problem. It will be even easier with 11.75" rotors. Thanks for all the parts links.

[HP2]

If your car is already set up for disc brakes and you have a functional master cylinder and prop valve and calipers, there is no need to swap anything out but the spindles and the rotors. Pin and slider brackets will bolt to any mopar disc spindle. As you  found, there is much more availability of the post '73 rotors.  Unless you are adamant about retaining the original configuration and willing to pay 4x the cost, get the later spindles, bearing, and rotors, swap them and enjoy your car.

If you also want to swap to the 11.75 rotors, then you will also need the corresponding caliper brackets. If you want to stick the 11" rotors, they can also be found in the larger bearing diameters to match the larger bearing spindles, than you can keep your original brackets.

[340Challman]

If your car is already set up for disc brakes and you have a functional master cylinder and prop valve and calipers, there is no need to swap anything out but the spindles and the rotors. Pin and slider brackets will bolt to any mopar disc spindle. As you  found, there is much more availability of the post '73 rotors.  Unless you are adamant about retaining the original configuration and willing to pay 4x the cost, get the later spindles, bearing, and rotors, swap them and enjoy your car.

If you also want to swap to the 11.75 rotors, then you will also need the corresponding caliper brackets. If you want to stick the 11" rotors, they can also be found in the larger bearing diameters to match the larger bearing spindles, than you can keep your original brackets.

Agreed. The car is being restored so most of the parts were going to be replaced anyway. Wasn't planning on replacing spindles, but the kit from Dr. Diff to move up to the 11.75" rotors is probably the winner.

Thanks everyone for all of the info. Always appreciate the knowledge.