[BAsque1]

Ok guys here it goes:
I changed the rotor and cap for original MSD-no change in the backfiring
Opened the in line gas this was clean no impurities in the wire mesh, nevertheless I blew it with compressed air just in case.
relocated the MSD coil to vertical position even though it says it does not matter, now while doing this I noted the ground cable for the coil was attached to the same bracket as the coil to the side of the fender, however, it was loose or poor ground connection. All was buttoned down nice and tight and test drove it and the backfiring appears to be gone. I am still skittish that this was sorted out but for now it looks that way. I will test drive it tomorrow again for a longer run and report back. Tks guys. Yes I do have a pointless electronic ignition I do not need the ballast resistor for this set up..
cheers
Lou