installing sl trunk lid spring

Help!
has anyone ever tried to install the OEM torsion spring trunk lid opener on a 107 car? I am restoring a euro 450sl and every operation has been impressively easy until this one. I've ordered the MB installation tool for this purpose, but have doubts about the proceedure. The manual makes it sound simple but the load is about 200lb. and the quarters are incredibly cramped! Is there a trick?
David

[devil]

about five years ago i attempted to do this same job
with a socket and extension. it worked, but i wouldn't
advise it. the damn thing came apart and left a dime
size dent and a huge bruise. my head healed but i
wouldnt try it again without the tool.