No start, nothing from starter.

[TupperWare]

Finally getting my single cam S13 back up and running. It's been sitting for like 2 months. I put the engine in and everything together. Go to build oil pressure and there's nothing. Battery has good charge, put a jump box and nothing. I bought a new starter and still. I checked the wire to the solenoid and when the key is to start it gives 12 volts. Then I turn it off then back to start and only goes to about 5. Idk if it's supposed to do that. I then jump the solenoid wire to direct power and it turns the engine. I've already tried jumping the starter relay but if it was bad I wouldn't be getting 12 volts at the wire. I've already cleaned the connection for the wire. I doubt it's an ignition switch because everything still acts the way it's supposed to.