I have Prothane poly bushings in my Fiero. While it looks like dielectric (spark plug boot) grease, the stuff Prothane sends is a really sticky, thick, nasty grease, that is near impossible to get off of your hands, or anything else it touches.
Since even that stuff wears away eventually, I drilled a hole all the way through the sway bar bushings, to the bar itself, and threaded a grease fitting into the metal strap that holds it in place. I then cut a circumferential groove throughout the bushing, to help distribute the grease. I hit it with the grease gun (I have Slick 50 grease in mine) at every oil change, or more often if it gets noisy. Works for me.
Since I installed poly bushings everywhere in it, I did that on my Fiero, on the control arm bushings as well as the sway bar bushings. It really made a huge difference in reducing the amount of spring stiffness.
97 LX, 4.6, Dynomax catback, Mustang MAF/intake tube and Aviator throttle body, Xcalibrator2 by Lonnie at BOC, 180 t-stat, Super Coupe wheels with 235/60/16's, Kenny Brown strut tower brace, Tokico Blues, Eibach Pro-kit, some strategically placed MN12 Performance polyurethane pieces, '02 Grand Marquis transmission
Submariners do it deeper...