Start by removing your stock front end and grill. Once removed compare the top bumper lip to the kits lip. Use the Dremel to cut off any tabs or protrusions that won't let the kit fit snug. (It's snug when the fender-lines match the kits lines) My B.W. kit required that the vents below the headlights be cut back 2 inches because of clearance problems with front bumper.
Buying a kit with large front-vents will cause lots of extra work unless you want to remove your front bumper. (not recommended)
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I went out a purchased a 90-93 big mouth front bumper for an Accord. I have my G20 bumper removed and need to campare the stock bumper to the new one. In your instructions you state "Once removed compare the top bumper lip to the kits lip".
Do you match the stock bumper to the inside of the new one or to the outside?
You also warned not to purchase a kit with large front vents. Would this include the Big mouth?
IF could you provide any additonal details or pic it would be helpful.
PS what about the rear bumper?
Juan