The least complicated solution ought to be tried first.

Especially in a car so old, you may have had a water leak that accelerated corrosion of the fuses in the panel -- did you try putting in fresh fuses?

Or, sometimes those ceramic fuses just break -- a small hairline fracture that's hard to see can stop you cold. You never know until you've replaced them.

This check would be the first thing I'd check before committing to a big mechanical job like replacing fuel pumps.

Good luck!!!