Advantages of aftermarket upper:lower control arms

Thanks for the input. I will round out the bottom of the cut, since I am still at that stage of the build. However, there is still a slight return at the top of the cut. I really didn't have to cut much at the top. My control arm support looked somewhat different from the one shown in your photo.

Here's the TSB info on that showing the gusset, it's over at hamtramck-historical. The links will show the full size version. This shows the issue on the opposite side from what is usually needing clearance for the narrow "V" shaped uca's, but it would work for both sides and you can imagine that cutting the mount back too severely could cause cracking at the other side.

https://www.hamtramck-historical.com/images/TSBs/1973/02-08A-73C page1.jpg
02-08A-73C page1.jpg

https://www.hamtramck-historical.com/images/TSBs/1973/02-08A-73C page2.jpg
02-08A-73C page2.jpg