I use the biggest actual chanel lock brand. I don't use the like you guys are thinking. That could hurt bad!
I assemble the spring over the shock absorber. Then in the same sort of fgashoin that you use a nut cracker,
I slide the handles that you hold, sidways into the coils of the spring right up into where the handles cross
I squeeze the pliers together, and with one hand on the handles, and the other hand on the side of the closed jaws I push the spring down. The spring cannot pop out using the pliers this way. Some one, unless your real lucky, needs to slip the retainer in for you.