Voltage Spike

[clemsonteg]

So I upgraded my alternator in my 70 C10 to a 94 amp 12si. I removed the external regulator and ran the factory brown wire to the #1 terminal and the 12v wire from the junction to the #2 terminal. I installed an 8 gauge wire from the battery terminal to a bus bar and an 8 gauge wire from the bus bar to a junction block on the passenger side to run my aftermarket add ons. The factory 12 gauge wire still runs to a separate junction block which connects to the battery via a fusible link. The fuses for the ammeter are still intact and connected to the factory ammeter.

Other than the alternator being somewhat defective, I can't figure out what part of my system would be messed up. I can hear a whine or strain, see via a multimeter, and watch the ammeter jump for no apparent reason. When idling in the driveway with nothing on but the engine, my voltage will sporadically spike from a constant 14.2-14.4 volts to 17 volts. Any thoughts or ideas where to start?

Some additional info: it didn't do any of this before I changed the alternator over, so it's definitely something induced by my changing of parts. The alternator is a reman from Advance Auto.