The rear frame was a weekend project, no doubt about that. Mark and I actually did a really good job of knocking out a bunch of work that weekend – we completely cut out the old rear frame, prepared the car to receive the new frame, and then welded the new frame into the car. It was nuts 😮 We went through countless blades on all of the cutting tools we used – the Sawzall, an air powered body saw, an air powered die grinder with cutting discs, and a cheapie 4″ angle grinder. All that stuff was used to break through a lot of the stock factory sheetmetal. I had always had the impression that these cars were tough, and that was reinforced that weekend – the stock factory crossmember and subframe are up to six layers in some places! In order to grapht the new frame into the old body, we had to weld the new frame into existing factory steel – and we wanted it to be strong – that part was very important. So, we basically projected a plane onto the factory steel where we wanted to put the new frame, and then cut on that line. Lasers are awesome 🙂 We basically created a ledge to sit the new crossmember on, that existed on top of the factory framerails. It was a challenge cutting the ledge, but only because that part of the stock framerails ends up being every which way but straight. So, we managed a reasonable facsimile of an L on the stock factory steel, and then set the new crossmember on top of it. At the end of the day, after getting it all tacked up – it was all square, straight, and level – imagine that 😀 After that, we spent a considerable amount of time reinfocing the stock steel so that the rear frame would be well supported. We made some 1/8″ steel plates that we welded to the stock framerails, that also welded to the new crossmember to give it a lot more rigidity, and to help the cute thin factory steel support the weight of the crossmember. When we were done, it all came out really well, and the crossmember was firmly planted in the car. What we did would have easily been sufficient to just weld into a street car, and go. Solid!