2007 Tundra 4.7 exhaust manifold question

Welp, I screwed the pooch. Due to some necessary exhaust work, I had to unbolt my catalytic converters from the exhaust manifold flange a few times. Being me, I either over-tightened them or backed them out at an angle because when it became necessary to unbolt them again, I basically destroyed the threads and the nuts (just the passenger side).

I did the best I could to re-secure them but the threads are in a bad way and while the truck is quiet enough at idle, it has that exhaust leak 'chugga-chugga' sound when I accelerate (probably a 3 or 4 on the obnoxious exhaust noise scale, but still).

So my question is, do I need to replace the entire manifold, or can those bolts/studs be replaced? The lower ends are star-shaped and I can see that the upper portion of the bolt is threaded (above the manifold fitting).

Any advice would be greatly appreciated.

 

I’m not home for another week but I replaced my catalytic converter passenger side recently.
Or I’d go out and look to confirm.
Those should be studs. Can you get the nut off and the catalytic converter off again?
If so, then careful application of torch heat and with a torx socket you should be able to unscrew and replace the stud. You want to heat the manifold, not the stud. I’d spray it with MOOVIT or any
quality penetrating oil first cause it will work into the threads with the heat.

 

Replacement parts ordered. Thanks.