Hi Jazn,
I was only able to screw on the end caps on my car with the tension unloaded. This means, springs removed. If you dont unload the tension, you risk not lining up the threads correctly, striping the threads. This would be an expensive mistake.
I, along with many others on this site, have done front end work. Lots of good posts on this and lots of members on this site to assist you. Just ask.
Please be VERY CAREFUL when working with the suspension and springs. Very dangerous. Need to use extreme caution.
Good luck!
Bob
bpossel (Memphis, TN.)
'71 280SL / '97 E320