Martin,
The "rubber" filler panels that go between the bumpers and the body on my Wife's 84 Riviera are starting to crack and fall apart. The only replacements I have been able to find are apparently made of fiberglass. I need to know if you guys have ever used them and how the fit is. They are fairly pricy (over $500) for the pair, front and back, but I dont mind as long as they are not going to be "junk".
Any opinions ??

I don't have a clue Bill, I'm sorry. One of these days those cars will be worthy of a nice "urethane" replacement. Right now, there just isn't a market for it I guess. Todays technology is SOOOOO far superiour it is a shame no one is making these parts for them.

Bill, you apparently are in the "business" so you may already know about this...There are a couple of aftermarket suppliers who specialize in the replacement pieces for Riviera and Cadillac. They are urethane and are essentially identical to original. I've used the ones for Caddys. I'm almost positive(but not willing to bet) that I've seen the pieces for Rivieras listed in the flyers. Usually, the products are available through the local aftermarket sheet metal suppliers who cater to body shops.

Did you try GM? I found a helpful parts guy who located the rubber fillers for a 78 Regal for me.Some parts guys tend to be lazy and wont look for older stuff.This guy also located a NOS rear bumper for a 1984 Subaru Bratt for me,said it was probably the last in the country sitting on a dealers shelf in Atlanta.Give them a shot. www.fredbeans.com (http://www.fredbeans.com)
Here is a company that has flexable reproductions
http://www.actionsalvage.com/bodyfillers.htm#Buick

Martin,
Thanks for the reply, the car is so nice, I will do what it takes.
Vette,
I have seen several listed, but when I called about them, I was told they were fiberglass instead of "flexible". Actually, I dont have a problem with the glass, as long as it fits and looks like the original. I would think it would hold up better and unless you get hit, it doesnt have to flex anyway.
Fine,
Action salvage is one of the places that told me that they were fiberglass...maybe I need to try calling them again. As far as the oem ones, I have several dealership contacts and all have struck out on GM's locator system. I am going to give FredBeans a shout first, then will probably go with the ones from Action.
Thanks for all your help,

I'd try the glass ones,at least they can be made to fit.Get either front or back,this way if they are junk you'll only be out half the money.No help at the bone yards? Mike