79 f250 starting issues
i got a 79 f250 that i put a new kwik wire universal harness in. The truck ran great for about oh 6 months and now I'm having trouble getting it to start. I thought the starter went out because it slowly stopped working but would work sometimes start if jumped off but then completely gave up to where it would only click once at the solenoid. Thinking it was as simple as that I left it sitting for maybe 3-4 months and I just got to changing it but it didn't fix the no start issue. I've done everything i could think of to troubleshoot it and the only thing I can come up with is a ground issue when I replaced the starter it would still only click once. Then I changed all of the old stiff hot/ground leads I could see, and now the one click turned into a fast clicking sound but still the starter is not activating. I've replaced the solenoid and still nothing has changed if I try to jump the solenoid I still just get the clicking sound and my multimeter doesn't show consistent voltage it's sporadic it only shows about 5-8 volts, I'm stumped and need help I hope you internet folk can assist thanks!!
it has a 400 in it if that helps at all



