The wire from the solenoid to the distributor can be eliminated. That wire provided 12v to the the coil on start only. You need a continuous 12v to the HEI, so you will have to replace the other wire on the coil with a 10 awg wire. That other wire is a resistance wire that drops the 12v going to the coil. From the coil that wire should go to the firewall connector and then to the ignition switch. I think I got that right I don't have the manual in front of me at the moment, if I'm wrong someone will catch it.

WOW! Near same question asked in 2 days!!! This is what I wrote in the previous post....

 The nice thing about the HEI set up is that you need only one wire, as WE all know!!! Easiest way I found is to go direct to the fuse block. My cars and an "IGN FUSED" spade right there waiting for my terminal... I, to be correct about it, always cut as much wire going originally going to the distributor in the donor car, and installing it into the recipent car. This way it has the proper connector to the distributor for that "factory" look!!! But then I removed all of that and installed injection....

 The short of it, just wire it into a good ignition source, power with key in the run and start positions only!!!

 Since I couldn't take a pic last night and I forgot about it till I saw this post, I took a pic of my '67 Grandes fuse box. Note the "IGN FUSED" terminal? This is what I used on several of my cars when I switched them to HEI. I didn't have an issue with the existing fuse, so that was left as was! The nicest thing, I have found, is that you run the "original" donor HEI wire to this spade, plug it into your distributor cap, and away you go... That's it!!!! This terminal is is all '65-'70 full size Pontiacs and Chevrolets that I have seen. If not, please correct me.

 Here is a pic as well............... Underlined in RED!!