Would I have to disconnect the MSD6A ignition (it's rubber mounted) before doing any welding on the "68"? I've heard that it could really screw the module if I don't. If I do, what would I have to dc?? Thanks Kevin

I have always been told to disconnect the negative battery cable and to put the ground clamp close to the area you are working on.

Bob

I didn't disconnect mine and it works just fine. I did as 69vert says and disconnected the battery and put the welder ground as close to the weld point as possible.

Why take a chance. Disconnect everything. When my roll bar was done, my Accell was left connected and was fried. The fabricator said 'never happened before' but that didn't save me any money on correcting !

I would suggest taking the battery out of the car. I have seen one battery explosion from welding. Many other times nothing happened but just one disaster is too many. Kevin

I concur with Rick. I mean at the cost of a new ignition box why not spend 15 more minutes to disco the bat and ignition. cheap insurance imo

I dced the battery and did the welding on the exhaust. Got about 100 miles on since then. Thanks Kevin

Remove both the positive and negative cables from the battery, you should then be OK.

I use this at work to protect the electrical system while welding on cars.
http://www.usatoolwarehouse.com/otc/otc3386.htm#P0_28