You have some serious corrosion issues. The tube is a stressed member of your suspension with pits and holes that deep (the tube is only 3/16th inch thick) I would worry about structural failure. You can buy a nre Pan Hard br mount, but I would be more worried about the rear end.
Just Google fully welded rear end, and broken plug welds to see how much stress is on the rear end.
I've never seen a replacement control-arm mounting bracket so I think you'd have to have one cut and welded in place. Actually, that may be the easy part just getting metal from Lowes/Home Depot and a air-tool grinder.
The harder thing might be welding to that rear-end and NOT blowing a hole through the pitted, thin axle tube. If you have a low performance motor and an automatic, you may be able to get away with just that bracket replacement. Still some risk in that though as they already noted.
Well, guess it's time to look around for a "used, but better than what I got" rear end. It is the weakest link in my setup, tranny is good, engine is good, it's a 350 out of 78 Camaro.
From quick shopping around, I see more 12 bolts than 10 bolts. I have a 10 bolt 8.2 in there now, if I got a 12 bolt, would I have to upgrade drive shaft as well?
Same driveshaft. Same everything other than the 12-Bolt itself. Has to be from a B-Body Chevy though for a direct and correct bolt-in. A '65-'70 Rear will fit your '66. They are a little hard to find and a little pricey as well. A 10-Bolt would be cheaper and easier to find and also remember the Ratios can be different which ever one you decide on.
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