If they are not seized or very sticky you may not get much improvement, just worried you go to all this cost and effort and be back where you started. Are the pads free in the calipers? a lot of people don't clean the pad land area (where they slide and also do not remove the paint from the sides of the metal pad backing material (it soon wears off but can gunk up the area. Best to just file the paint off and coat the sides and back of the metal with Coppaslip or similar. If the pads are free the pistons should not creep. The only other thing I have seen done with storage vehicles is to tie the brake pedal up to the steering wheel but again if the pedal return spring is in good order logic says that does nothing?
