I have Heacock Classic (AMIG) on my '72 Dart. So far I've only had a couple of towing reimbursements, but they were easy to deal with.

I ended up going with them since they were the only ones who'd write coverage with a nitrous system of any size. They also covered me while the car was under construction "at least 80% complete". Also I have emails confirming that I can run an occasional errand while out for pleasure use. As usual it has to be in a locked garage when not in use.