Yeah no need to destroy that bolt just go through the painful process of manually unscrew the bolt the first time. Then reinstall it backwards.
As for the arm I don't know if it is threaded or not. It might be but there is a pressure applied from the springs and the brake assembly onto this lower arm. Therefore even if it is not threaded it will make the removal of the bolt difficult. You might want to put a jack stand underneath to release that pressure.

 

I have done this job twice. Both times the exhaust was in the way because I didn't reverse the bolt direction until after the second time. The first time was to install H&R springs and the second to install K-MAC camber bushings.

The first time I got the bolts out without removing the exhaust by physically lifting it up out of the way and putting a jack stand under the muffler. Since as noted there is pressure on the control arm bolt, even with the floor jack under the control arm to help relieve the strain, the bolt must be turned out all the way and not forced out with a punch and hammer. You might be able to adjust the jack pressure and wiggle the bolt out the last bit once the end is past the first side of the control arm. The control arm is pressed steel and the thickness is thin enough to catch in the threads of the bolt but is not threaded per say. This way worked but the exhaust still interfered with the bolt and made extraction difficult as it was impossible too turn the bolt more than a flat or two at a time and I don't think I could get a socket on but don't really remember exactly how I got the bolt but just that I did get it out. When I did the driver's side it twisted the exhaust in the rear clamp and it was crooked when I was done. I fixed that by loosening the clamp, straightening the tips and re-tightening the clamp.

The second time I knew it was worth the time to get the exhaust out of the way. I used a 23" mechanics pry bar to pry the rubber donuts off the muffler hangers and let the exhaust drop until it was low enough to work over top of it. Still a tight go but better than before. I supported the mufflers on jack stands with a block of wood in between to reduce marring the mufflers. I can't remember if I had to remove the mid section hangers but I think maybe I did to get the exhaust to drop enough. Do not just let the exhaust hang put something under to support it. The bolts were installed from the front so I should not have to go through this again if I have to remove it. The donuts are a bit of a fight to remove and re-install so be ready for it. Wear leather gloves!

This is the challenge of doing your own mechanical work and overcoming obstacles is part of the satisfaction when a job is completed.

BigBadLarry GL getting the bolts out and the springs in. You can do it!

 

Thanks for the advice and words of encouragement!

So I managed to finally get one bolt out - passenger side. Took a sawzall to the bolt and used vice grips - all per crazy1eye suggestion

The spring came out right away, and it was easy to replace the spring pad, but then I faced the next challenge:

Lining up the arm to screw in the new bolt. It seems to be about 1/2 inch off.. looks like more headaches ahead.

 

Make sure the spring is properly seated in its perch and that you put the spring pad correctly on the top of the spring. Jack the lower control arm up with the jack at right angles to the car so that you can push it in or pull it out to line up the bolt holes in the control arm with the mount. Don't be afraid to muscle it into position and jack it up the last bit. Use a large drift to align the bolt holes and then slide the bolt in from the front. Are you using a floor jack on wheels or the car's jack?

You should not have this problem on the driver's side. Undo the muffler clamp between the muffler and resonator and let the exhaust drop out of the way or lift it out of the way whichever is easier for you. Support in with a jack stand. You should then have room to get the bolt out from the rear. I think you will need a torx shaped E12 socket to undo the muffler clamp that you can get from an auto parts store.

 

Well, the deed is done :-) replaced both rear stock spring pads with 17mm pads to better match my H&R springs.

It was not too bad to get the arm lined up - just a bit of persistence and a little muscling, as you said mort. I inserted the new bolt from the front - got the tip started and socket wrench did the rest (not enough room for the impact driver)

Driver side went a bit faster, but still a huge pain getting the bolt out. Used the same procedure of cutting the bolt w/ sawzall and using a new bolt from the front.

In the end, I probably wouldn't do it again (on jack stands at least), but it is rewarding now that the job is done.

All that's left is drive it around cheers and thanks for the tips!

 

 

Ya it's a bit of a pita to line up alone on jack stands, but hey just think, it'll be easier next time