Maybe it would be a good idea to use carpet to finish off the install. Everyone always enjoys an install that looks like it's been around since the early 90s. When was the last time you've seen an install that was done in carpet? Most of the cars you'll see in the car stereo mags use different types of materials for their install rather than carpet because they've stepped up to the plate and realized that the car audio industry has evolved and is capable of offering new concepts and ideas and not things of the past. Basically my advice to you is use your imagination.