Wow...I don't ever think I've seen a car with a roof that rotten, that's a total replacement, there isn't even enough metal to think about welding anything on to! Would be a nice car when finished, but I think it's already finished...
Found the possible donor: https://portland.craigslist.org/mlt/cto/d/1965-pontiac-lemans/6697589584.html
Placement of the ignition switch on the left was an allusion to GranPrix racing. The drivers would be poised along the sidelines . The cars would be sitting on the track. At the start signal,the drivers would sprint to their cars,leap in,start and go. The ignition on the left side of the cockpit worked more efficiently as the driver's right hand was on the shifter as the left engaged the ignition switch. John DeLorean was an afficianado of cars that handled well,hence the Pontiac Sprint overhead cam valve six cylinder Tempest Sprint cars. And,tellingly enough, the GTO was a LeMans with a handling/power "package" All GTOs were Lemans until "GTO" came into it's own right as a separate series in 1966.