stereo in a bus

I am going to be installing a bus into a bus that has no stereo. I will likely be going into the dash which is mostly plywood covered with padded vinyl. The question I have is how to make the edge of the padded vinyl look nice. I am pretty sure I can just cut the perfect size hole in the plywood and the vinyl and then use the sleeve to support the stereo, but the sleeve will be tight against the plywood and I don't think the flange on the sleeve will be big enough to hold down the vinyl. I was looking at a steel trim plate but I don't think this guy wants screws showing which will likely be needed to attach the trim plate. Unless I use some nicer looking screws, but that might not be acceptable. Any ideas on how to make this look really nice? Also does anyone know what type of vehicles do not need adapters for antenna's I have a replacement antenna that is meant to attach to an existing antenna wire and you just cut off the old antenna and connect the cut end to the new antenna. Since there was not an existing antenna on the bus, I want to just cut one out of a vehicle at the salvage yard, but I want to do so out of a vehicle that does not need an adapter if there is such a vehicle. I have a JVC Head unit if that makes a difference. Thanks a lot for any help.

mark your hole for the cage on the vinyl and then cut an "X" in the vinyl from corner to corner of your hole but stop about 1/2 to 3/4 of an inch from each corner depending on how thick the padding is. fold back the vinyl and cut the hole for the cage in the wood and once thats done fold the vinyl into the hole and slide the cage in and bend the tabs. once the radio is in it should look decent but if you can still see the seam then make or buy a thin trim plate and sandwich it between the vinyl and the cage. as far as the antenna, get a older ford antenna 2005 and older and you shouldn't need an adapter good luck and use common sense

That pretty much explains everything I need to know! And by the way, I like the "use common sense" line. I have always considered myself to have a high level of common sense (not to sound boastful), but in my endeavors I have found that common sense is not so common. Thank you very much for the help.