FYI-I found a fix for my 96 Century plastic Leg/Knees Bolster coming loose/off and it worked well.
Thought I'd share for anyone having the same problem.

Only took a pic after done.

There is a heavy metal plate that is screwed to the bottom of the dash and on top and has a firmly attached non-removable(suppose to be) plastic cover.
I believe this is called the Leg/Knees Bolster(deflection) for in case of an accident to reduce injuries, added to later models perhaps when the air bag were introduced.
The cover has I think it was 7 plastic attachment legs that are just melted into 7 holes in the metal. These legs break out of the metal over time(seen them this way in the salvage yard too).

Previously when I bought the Century about 4 years ago, I had taken the metal plate off and the plastic front cover came off.
I had then used a hot glue gun to glue the plastic. Well this failed recently so I had to repair it again.

This time I believe I did a very strong repair that should last the life of the car:

I used 7 3/8" rivets- 1/2" long, 7 back up washers and used a paint pen to paint their heads black(or the color of your cover, paint before install is best.

I removed the metal panel using 7mm hex driver. There is also a small Philips screw inside the ashtray opening, also remove the ashtray by pressing down the silver metal retaining tongue at the top and the ashtray wiring must be unplugged as well.

Using a small-pilot hole drill bit, I drilled the plastic cover from the backside through the center of each of the 7 falling apart plastic attachment legs.
Then I re-drilled with a larger bit that the rivets can fit in.

I then inserted and attached the rivets one at a time WITH A BACK UP WASHER on the backside, otherwise the rivet is too small to hold in the larger metal holes. Hold the metal and plastic surfaces and rivet and washer tight together when using the rivet puller to get a tight fit.

Re-attach the metal panel. The rivets do show now but I don't think there is a solid fix without something showing and it doesn't look bad and isn't very visible since it'* by your knees.

Take care

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