Got a call to replace some 2'x4' 4 lamp florescents that are built right into the finished drywall ceiling at a commercial building. Looking at the fixture it appears to be the same as a lay in type. I talked to the guys at the wholesale house and they say they don't carry a specific fixture but they think that some type of trim may be available that fit's around a conventional lay in.Anybody here familiar with a product that is already assembled as one unit and not something generic that can be pieced on to a regular fixture? Thanks.