70 & up flat reg correct? Sounds like classic bad reg or reg not grounded. Assuming the new one is good & you grounded it to bare metal on the firewall then I'd take off the 2 field wires from the alt & take off the triangle plug from the reg & (1) jump 12V to either of the alt male field terminals and (2) 12V to the "top" male bullet terminal of the reg triangle with it facing up like a pyramid & (3) jump from the other alt male field terminal to the "side" reg male bullet terminal & see if it charges like it did before with the slight discharge at idle which is normal for our alts'. Might check that the eng is grounded well to the firewall with one of those metal braided straps but with the wiring jumped if it's still acting up then either the alt or the reg is bad (likely the reg). Holler how it goes. Need 2 double female "bullet" connectors to use on the reg bullet terminals