From Terry Herrin:
I had a hard time finding a place to put my Blaster SS as well. Like you I put the 6A behind the battery. I'm running Magnecor KV85 wires, and the coil wire is long enough to reach the SS. I also used an Accel wiring harness, part number 140021AH, to connect the wires from the stock coil so I can easily switch back to the stock ignition.
From Ron Wong:
Put it on the fender wall next to the PCM. If your cruise control is in the way just shift it down toward the headlight. I mounted my blaster SS there and have had no problems with it. That way my existing coil wire reaches with no problem. I use the MSD Super Conductor 8.5 mm wires. I took the MSD ignition wires and extended them all the way around against the firewall and around to the right fender. Right along there is where I have the harness. I also set up the wires going to the stock coil so that I could disconnect from the SS and go back to the stock coil should a problem arise.