Im gonna install my msd 6a with blaster SS coil also my car has the external coil already. Just wanted to make sure I'll get it right heavy black goes to battery negative. The heavy red goes to battery positive then I cut the wires leading to the stock coil off splice the yellow/black and yellow wires together and connect them to the switched 12 volts on the msd box. Then take the black/white wire and connect it to the white wire on the box for timing. Then the black(-) and orange(+) connect to the SS coil then I take the coil wire from the dizzy and plug it into the new coil is that all or did I miss sumthin. I was also wondering if anyone with a fairly stock car who has a MSD 6A or 6AL with the blaster SS coil would also write me back and let me know if it helped and how long you have had it on and if youve had any problems from it (damage to the engine, bad idle, bad gas mileage, etc) thanks. 
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