I did the same thing on my 69. I bought the following items:
Junkyard HEI (with the 12V supply connector)
Accel HEI Supercoil
Accel Cap and rotor
I pulled the resitance wire from the juntion block and carefully removed it from the spade connector. I them soldered a 12 gauge wire to the spade and the HEI connector. Replace the wire in the junction block, Drop in the HEI, and hook it up.
If you look in Wes Vanns Tech ref section he goes over an HEI conversion.
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