well having gone through this,, REALLY check those rails. there is a good chance you can patch the towers, but you need to cut out the area and check the top and back side of the rail in that area for any pin holes. patching that large an area will most likely get you into the upper suspension mount.
there is a re-enforcement in the shock tower that ties into the upper suspension/spring perch.
If you don't have to touch that you might be able to get away with cutting the spot welds from behind then cut out the cancer as far down as you can go.
its not going to be easy because the engine cradle is in the way. you want solid welds in that area.
I know my friend that does metal work would say he wants to pull all the spot welds and drop out the engine cradle out of the way and get the lower shock towers exposed to the spot welds that attach it to the rails, then decide if he should just patch it. after he did that, he would cut a window from the rusted out area to expose the back side of the rails, if he sees any softness, he would measure and pull the tower out, then as long as the rust was limited on the rail he would patch the rail and then graft in a new lower shock section from a donor with the shock tower off the car, then put it all back together.
also now your getting into the Grey area in these cars because the VIN is attached to the shock towers.
the problem is most donor cars are going to have the same problem, so now your talking about fabrication. i don't know if anybody every took a 1970 shock tower and really looked at it to see what could be done. I wish dynacorn would reproduce them 71-73 , i ended up getting the front clip from a 73 convertible and grafting it onto the car.
