i have an A108 Van. the front brakes r discs from an 87 Durango. the rears r 11" drums from a B van. the pedal height seems to fade back. maybe "fade" is the wrong word. the pressure is always solid. the distance i need to push the pedal to get to the solid pressure gets longer. i can get it up where i want it by getting under and adjusting the rear brakes up tighter. i have developed a habit of double pumping between adjustments and the pedal comes right up. maybe i have the auto adjusters in wrong? maybe i don't back up enuff? maybe i have the parking brake set too loose?

is the auto adjuster cable supposed to route along the forward shoe, or the rear? it the action of turning the star wheel supposed to happen by pulling up on the star or pulling down? maybe my star is worn down?

anybody else had this predicament?

You have diagnosed it perfectly. When the shoes touch the drum slightly, the hydraulic fluid doesn't need to move them before applying pressure. If you can build a rock solid pedal with a double pump, and then it holds, then adjustment is clearly the problem. If you then adjust the shoes tighter and the pedal feels nice and solid, you have proven the problem. A loose parking brake cable doesn't affect the shoe adjustment-- it's the other way around: if the shoes aren't tight enough against the drum, it could affect the parking brake movement in the same manner that it affects the pedal movement (because the shoes have to physically move before the mechanism can apply pressure.)
Sadly, that's a trick question. Some cars were built one way, some the other-- I recall there was a difference between mid-60s and early-70s A-bodies, and it wasn't easy to remember which was which... it seemed easier to just use the brake spoon to adjust a couple of clicks and rotate the drum (or tire) while attempting to judge by whether it was getting tighter or looser.

If you installed the entire axle and brake assemblies as a unit, it ought to be right. If you mixed and matched, I don't know.... but it's not impossible to figure out. If the shoes continue to get looser as you drive, perhaps backing up (to engage the adjusters) is affecting the star wheels the wrong way? They shouldn't need adjustment very often, especially in the rear. Try swapping the star wheels from left to right side. If the need to adjust goes away, you've found the culprit. (I'm assuming the star wheel threads are well-greased, turn easily by hand? If they won't turn by hand, no self-adjuster mechanism is going to be able to turn them, either.)

- Erik

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Lots of early Valiants and Barracudas have crossed my path.
Also a handful of other toys for variety now and then.