My '95 SSE has the rear end a little low. How do I know if the springs are bad. I can't tell from the ride, but occasionally when I go up and down an incline, the rear touches the ground. Is there a specific height that I can measure? If I need springs, do I replace them with stock springs or after market? Which ones? Do the struts have to be removed to replace the springs?

How many miles on your car? I've seen springs over 250K that are still good and ones with 150K still hold weight.

Maybe your struts are bad?

I have 130K miles. When I bounce the rear, it comes back right up. I just noticed the rear a little low.

http://www.williamwren.com/struts/elc.html

Your struts may be good as far as gas charging is concerned, but the ELC portion may be shot. Or your level sensor may be misadjusted.

Where did you get the red rubber bushings for the tierod ends?

they are made by Energy Suspension, and I believe that Adavnce has them

Autozone carries them on the shelf. Front and rear. These aren't for the tie-rods. Those are the sway bar endlink bushings. Polyurethane, not rubber. Get the front kit, and buy the universal kit for the rear. Prices and part numbers are listed here with pics if you do a search on "energy suspension' in the 92-99 forum.

I'm going to jump in here.. My 94 Bonneville SE had the same issue of a slightly sagging rear (due to weak springs as it does not have ELC) with only 78K miles on the clock. In my case the struts were way too soft so I went with air struts. A mere 20lbs of air gives a nice, slightly tail up look and a tremendous increase in control and ride comfort.
Not to mention that I can now load the car up with people or cargo and raise the back up to normal with a trip to the air hose....
Rob

jr's3800 did exactly the same thing to his 95 SE.

Yep,
I took JR3800'* lead and was very happy with the improvement. He even sent me tips on how to do the job so I figured I would jump in and do the same.
Rob