Both of my darn door panels in the 99 have the infamous crack all of a sudden inthe door panel about 3/4 of the way down from the front right at the glass and are growing straight down!
I found numerous posts about this but none really explaining why this seems to happen only to the 98-02 cars?? My 99 has only 30k miles on it while my 95 has 140k miles and not a single crack on them!

Guess I have yet another project to pull them off and try to repair them

 

Well this was my best try at repairing the cracks..removed both panels, and now I see why these crack as there were several more starting right where these square tabs protrude off the panels, should have been designed with curves instead of 90 degrees squares edges, I supposed the LT1 cars do not have this design on the underside....should have snapped a pic with them off...

Anyway, found that JB Weld is darn near the same color as the door panels, drilled tiny holes at the end of the crack on each panel, mixed up some JBW, and caked it on the back sides over the crack and the other places that looked like they were starting to crack, then smeared a thin layer over the top surface....doesn't look as bad as it does in the pics, but sure looks better than a crack that was doing nothing but getting bigger by the day.
Did both sides:

 

I've found that the vinyl paint from The Eastwood Company is available in a shade that is almost a perfect match for the stock interior gray, at least if GM was still using the same color for the vinyl in the 99 that they used in my 94. I've used it on the A-pillar, a radio blanking plate, cigarette light cover, etc.

http://www.injuneer.com/images/photo.../DCP03464a.jpg

 

It looks to be the same color as my 95 so i assume they are the same. The jb weld actually matches quite well, after 24 hours the surface is still slightly tacky and you can rub it with your fingers a little and it will dull down till you have just the right amout of gloss to match the gray plastic gloss.
Do you have a color code for the Eastwood paint for the gray in case i need to do this again?
Interior looks nice in the car!

 

What Eastwood sells used to be SEM, relabled. Now they sell it under the SEM brand, so you could buy it anywhere.

My 94 Formula has the code 12 Graphite interior. The paint that matched best is the SEM 15303 Graphite Vinyl Interior paint.

http://www.injuneer.com/images/photo.../DCP03460a.jpg

I also used the same color to make some dash blanking plates for a friend's 30th SS convertible, which had the white leather interior, but the dash was still a dark gray. Matched his dash too.

http://www.injuneer.com/images/photo.../DCP03866a.jpg