1978 Aspen R/T 318 4 speed

After careful consideration and a lot of poking with a screwdriver, I've decided I have to replace the frame rails instead of repairing them. Looks like it's time to drop the k-frame. Any hints or suggestions on an easier way to do this would be greatly appreciated. Also has anyone ever used the frame cap repair parts and if so would they work here.

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Author: Ed Dorey