Not getting 12 volts to coil

Since I got 1.5 lower volts after the bulkhead connecgtor under the dash than immediately before in the engine compartment, I'll work on cleaning them up or replacing. Frankly, nothing looks that bad. I see oxidation on the flat bottoms leading up to the fuses, but the copper looks ok.
So I bought some welding pins to try to clean the insides of the connectors out. Should I bite
the bullet and take the individual connectors out? As you said, I'll have to take the seats out
to make access easier.