That sucks about the freeze plug. I have started using the brass ones, and use the copper gasket goo that has an applicator/dobber thing that is part of the cap. I'm glad you have the car about done. I had the exact same thing happen to a 71 Challenger that I had traded for. Replacing the freeze plug in the back of the motor turned into swapping the 904 to a 727, swapping the 7 1/4 to an 8 3/4, TTI headers, new exhaust, a Comp cam, LD4B intake and an Edelbrock 1406, 15 x 7 Rallye wheels and new tires. From a bad freeze plug! LOL