98 s10,

been trying to trace down a voltage drop, new batt. cap & roter,
and fuel pump, and pos. wire leeds . checked all grounds.
have 12.4 v at batt, altanater, fuse block .

have done a fuse check
and disconected batt. and hooked up test light and it lights up, took out one fuse at a time and light did not go out at all.

what am i missing

Thanks for input