I'm just about finished installing Ryan_RS's and have already done my own. In neither case was it necessary to use one.
Just turn the suspension upside down to the ground and apply some pressure as you're loosening the top bolt(which now faces the ground). Once it's undone, the spring will pop some, but not a lot. Not more than 30lbs of unsprung pressure I would guess. The rear suspensions hardly pops at all. It would be absolutely ridiculous to use a spring compressor on the rears. It has to be less than 10 lbs of spring pressure.
Good Luck!
Jason 98' Eagle Talon ESi-T Mitsu Super 16g Turbo(HRC)/Custom FMIC
Like Jason said....I didn't use one at all either. I just put the strut assembly on the ground, put a heavy duty blanket over it and went to town with an impact wrench. It hardly even popped...I was surprised.
Well, me and a friend installed my maxspeed coilovers on sunday, and didn't use a spring compressor at all. Took us about 5-6 hours (used impact wrench some for taking apart). I just wish the fronts were as easy as the rears...lol. Time for that $15 camber mod (actually, cost me 30 bucks just for the bolts, washers, and loctite for this mod, gonna do it tomorrow or next day).
Brandon '95 GS, Auto. AEM CAI w/ bypass Maxspeed Coilovers Pilot FU STB Best ET: 17.243 @ 80.67 mph
Brandon '95 GS, Auto. AEM Cold Air w/ bypass valve Front Upper Strut Brace Maxspeed coilovers