Stripped threads on Front Suspension Member Front Brace.

Long time reader, first time poster. I appreciate all the knowledge within this community!

So awhile ago I replaced the front stabilizer bar bushings on my 2010 Prius. When reinstalling, I don't know how it happened, but I stripped what one of the retaining bolts screws into. I could turn it until it sat flush with the brace but I couldn't torque it to spec without it getting more loose so I stopped messing with it. I think I was about to torque it to about 27 Nm (20ft-lbs).

It was a late night and I guess I figured because I was able to torque down the other 3 to spec it'd probably be fine. Anyways, I somehow forgot about it until just a couple of days ago and figure I should get around to repairing that.

I'm seeking confirmation on how I'm planning to repair it. First I was going to see if I could repair the threads by tapping them with the original size. If that doesn't work, I was planning to drill it out and tap in a helicoil. Is there a different way I should approach this?

Also, does anyone know what size threads it is? I did some digging online and think the part number for the bolt is a 91552-L 1230, but the local Toyota dealership doesn't have it in stock and couldn't tell me any info about size, thread count or grade.

And finally, please tell me if I'm an idiot and I need to repair this asap. I may have put 2000+ miles on it since doing this "repair", so I figure it's been fine this long, but I could be overlooking something (like structural integrity if I got in a crash).

 

Ok, so I went out and checked on it again, probably should have done that before posting. Three of them were torqued to spec at 67 ft-lbs, the fourth (see arrow) was not at torque and spun a little. I remember from before that I wasn't able to ever get it to spec without it still spinning and I didn't want to damage it further.

I slowly incremented my wrench and got all the way to 64 ft-lbs. So I'm going to say it's fine and I'm not going to mess with it unless I need to take off the front stabilizer for any reason in the future.

I am still curious to know how any of you would repair the threads on the Lower Suspension Arm sub assembly, would you try to repair the threads or replace the full assembly?