Installing Prothane Bushings...

I had poly in my control arms of my last 5.0. They were great on the interstate but I hated them on roads with potholes. It was a rough ride and the squeaked a lot. I don't know if I'm right but I would use some marine (waterproof) grease on them. I think its in a green tube, if your using a grease gun
Edit: Mine might have been urethane(eng suspension)

No grease on the isolators. grease all of the other busings- sway bar, control arms. etc. You don't have to use their lube but you do need to use grease specific for poly bushings, you can also buy Marine grease. just look at the tube and make sure it works with poly bushings. Word of advice though. I do not recommend using poly bushings on both ends of rear lower control arms as they tend to cause excessive bind and tear up torque boxes, which is why I use Maximum Motorsports LCA. Same for the rear upper control arms. I leave the stock ones in with rubber bushings.

For the isolators, tape them to the top of the spring so they dont shift around.

Just my 2 cents.