Yes they can come off and they should just clip into place.

I assume you mean the stock black "vent" pieces...
Hood: you should be able to catch an edge in the front or the back of the little vents and then pry them out. I might recommend putting a small, round screwdriver through the little holes and using that to pry it out.
Sides: again, you should be able to find an edge near the top of the full scoop. You will have to take the whole scoop out: painted and black vent piece all together. I think you can separate the black piece by removing a screw once the whole thing is out, but I'm not sure.
In both cases, you wanna be careful prying so that you don't mark-up your paint. Use a small flat-head screwdriver and maybe put something in between... or if you have something rigid, flat, and plastic?

Good luck, let us know how you make out!

__________________
YELLOW JACKET = 1998 Chrome Yellow V6
POWER: BBK CAI, TB, UDPs; Bosch Platinum +4 plugs
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DRIVER: Jonathan, 6'2, 190 lbs
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and my 1st baby on the way...
