Would someone be able to tell me what is involved in replacing the black metal insert between the T-tops on a 1989 IROC?

Removing the t-top weatherstripping seal, pull the 6 screws that hold it down, pry it away from the adhesive patch that is under the areas where water can get under. It is pretty involved and will more than likely destroy the weatherstripping for the t-tops in the process. So unless it is badly rusted and leaking or something, make sure you have to do it.

Well, I just bought one on Ebay because mine has the paint bubbling up in a couple of places. I may wait a while though to install it after reading your description of the installation process.

I just removed, refinished and reinstalled mine. I created a mess by deciding to replace the ttop weatherstripping. After removing that, I saw rust and thought it was on the car. I removed the center piece to find it was only that piece that had rust. The car looked like it was just painted under it.

I removed it, cleaned it up and repainted it with Duplicolor Trim Black paint. Came out looking really good. Be sure you take note of how the piece is set up with sealant before you remove it. When reinstalling, there will be gaps between the center bar and the body. be sure to apply the sealant liberally at all 4 inside corners to fill up this gap. Additional sealant will be needed when reinstalling the weatherstripping. It's almost impossible to replace the bar and keep your old weatherstripping. It will be a big job, so enjoy.

Thanks for the description of what is involved. I'm glad I didn't begin taking the car apart yet. Sounds like I better have a professional body man do the work.

I'm not sure I would want anybody else doing this now that I've been inside it. I would be afraid that they wouldn't do it correctly. Do your research on the weatherstripping replacement, clean up the area really well, examine how the factory sealant was applied to the t bar and remove it. The reverse is required for install. Check this link for replacing the weatherstripping.

http://www.superchevy.com/technical/...rip/index.html

Thanks for the advice.

I purchased a t-top insert from a guy on ebay who said it was rust free and nice. it is rust free but not nice. there are dents in top center post that would show after installation. We don't see eye to eye on the definition of "nice". anyway I'm stuck with a rust free dented insert that I can't use so now I'll have to keep the one I have and look into repairing the bubbling paint from the lower section of the existing insert.

You could probably fix the dented center piece if you wanted rather than trying to fix something that has rust starting on it. Mine had some dings as well as rust and I fixed it. Blasted it first in a glass beader, Ospho treated it, bondo/filler equivalent I use the dings, sanded smooth and rounded the edges if I had to anywhere, then painted. It looks fine if you spend the time to make it look nice. At least that way you won't have to worry about the rust coming back.

You know I never gave any thought to trying to repair the part, I was so irritated about how bad it looked when I opened the package especially when the guy who sold it asked me if I wanted some kind of perfect car and that nobody will be climbing on top of the car to inspect the dents in the t-top bar.
I think repairing this might be possible and I think I'll give it a try.
Thanks for your help. Becareful what you buy on Ebay.