For the rear plastic one, insert a thin blade screwdriver in the slots (two on each side of the frame about 1" from the top/bottom) and push back the tab while applying pressure to pull the frame away from the license plate. There are 4 snap tabs on the frame that just need to be pushed back to disengage from the body slots. Be careful, they're not very sturdy.
The above answer is apparently for the rear, but I'll leave it there. The question was for the front, so... the front C5 license filler has a wide tab at the top that slips up into a slot in the front nose. It is held up there by two small Phillips head screws at the bottom of the filler.
If you get on the ground and use a flashlight to look into the thin gap between the bottom of the filler plate and the bumper recess, you should be able to see a screw a couple of inches in toward the center from each lower corner.
Use a small Phillips screwdriver to remove the 2 screws. Then you pull the filler plate out at the bottom just enough to clear the bumper and then pull it down to disengage the top tab.
If you need a new filler, the current part number for a GM replacement (unpainted) is 10288540. They are around $110. If you do a Google Shopping search for that part number, you should be able to take a look at some pictures of one so you can see the wide tab and 2 screw holes. There are usually some on E-bay.
Or, here's a picture I put in my album. Copy the link into your browser's address window and hit "enter":
http://i59.Photobucket.com/albums/g302/porxter/corvettelicensefillerplates001.jpg
A person can remove the front license plate cover on a 1990 Corvette with a screwdriver. The plate can then be replaced with a custom plate or a state plate if required.
There are screws holding it on. Un-screw them.
Lay down on the ground in front of the cover,look between the cover and the bumper and you'll see two Phillips head screws.remove them and your cover will be off.I just did this.
The 1990 Chevy Corvette front drivers side speaker cover will need to be removed. Remove the speaker retaining screws. Remove the wiring harness from the back of the speaker.
There are two screws on the bottom of the cover. You should have just enough room to fit a screwdriver in between the nose of the car and the cover without scratching the paint. It might be tight, but the cover should give enough for you to get tools in there.
Are there people that use the front license plate still? lol Well taking them off if you are using them is quite easy, get a screwdriver and take the bolts out. Now if you have a custom plate holder you can get a detailed answer by visiting smokinvette.com. Good luck!
FYI I have an 84 vette and the front end is now worth a fortune as I never popped out the front plate section and left it original - there are under 300 left with original front end. Food for thought if you plan to keep the car long term.
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Remove the front cover of your 1979 Chevy Corvette radio. Remove the radio retaining screws. Slide the radio out. Remove the wiring harness and the antenna cable from the back of the radio. Reverse the process to install the new radio.
== == == == you don't it's molded int to the bumper.
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