Can you use stock wires with an MSD 6A ignition ? I currently have the MSD 8.5mm wires ,but I am going back to the stock look but I still want to keep my MSD box. I'm concerned that the wires will break down.

I wouldn't because of the high ohm resistance. MSD recommends spiral core type wires, they have a low ohm and are very good conductors. Solid core is a no-no. Hit MSD's site, they have a pretty good online tech forum.

I thought the big thing with the MSD boxes is that you have to have the helical plug wires. so my guess is that stock wires are the solid core ones, but dont quote me on that.

Stock wires use a carbon-impregnated film of some kind and it's not spiral wound- just a straight shot down the middle of the wire. Tear one open and you'll see.

I've used standard wires with MSD boxes before and not had too many problems in the short-medium term. The first one to go in the long term seems to be the wire from the coil to the distributor, I guess since it's doing 8X the work as the rest of the wires. It doesn't really "burn" them, it kinda makes them....... well........ this may sound weird, but they sort of pop. A little break in the insulation with some fiberglass fluff sticking out and that's it- it don't work no more.

After all that is said, doesnt mean you have to slurge for the $80+ msd set. You can get some 8.5 spiral wound from Accel for like $30.

MSD has a new version of its Super-Conductor wires that are black to give a more original appearance. You might want to check into those, although any quality wire will do what you want. Good luck.