An quality aftermarket camshaft with an exceptionally mild grind with roller cam followers will end the flat-cam syndrome faster than you can say "Harmonic Balancer". Something like Bruce Crower's works. Several brands of engines had the sloppiest cam timing a person can conceive of and while 2 degrees of advance or ****** won't flatten the lobes sloppy heat treating will. The 454 series engine, along with Ford's 460 are members of the sloppy timing -other reality- cam lobe profile club. The old FE class Fords, 331-360-390 engines were charter members, the 406 and 427 engines were different animals, but Ford returned to their evil ways with the 428. MoPar ain't exempt. The L3 440 cylinder head valve seats (induction hardened) might have had department supervision by a Borneo cannibal.
Keep in mind unless your rig is stored where there is no 120vac power, your search for a suitable pump is not limited to 12-volts. An 80-PSI bypass (relief) valve is recommended for larger capacity units.