Will 80s calipers fit on a 74 d100

[moparkrazed]

Hey guys, at my wits end with brakes. I've replaced rhe booster and mc a few times. It seems the 80s model has the most pressure compared tk the 80s model. But both combos are not making the calipers work. Im thinking my issue is the actual caliper, they are new from autozone but that doesn't mean anything these days. When bleeding the brakes the 80s booster and mc shot the fluid out the bleeders forcefully but wouldn't move the cylinder in the calper. The 70s barley has a trickle, but neither allow my front calipers to work. Any thoughts or anything I left out?

 

[7mopar]

I quite the pressure power bleed long ago.
I have yet to try the reverse pressure bleed but have been told it works great. I vacuum bleed if at all possible. Some 70's system was gravity bleed only.
Problem with power bleeding is activation of the over center valve if so equipped.

 

[MILO]

do you have the calipers on with the bleeder on the top

 

[65 sporty]

do you have the calipers on with the bleeder on the top

I thought the same thing