Hello Mike,
There is a simple trick I use to install gas filled shocks. Place a hose clamp around the rubber boot. Compress the shock. tighten the hose clamp so the shock stays in the compressed position during installation. Once you have the lower mounting in position release the clamp slowly and guide the top of the shock into its mounting!
I alwasy angle the lower mounting bolts on the front shock about 20-30 degrees off vertical prior to intstallation. Also be careful not to release the front shocks until you are ready to guide the top of the shock into the mounting hole. If you miss the hole and hit the inside of the fender you could make an inside out dent in the body!