I used bed liner on the boards of my 40 chev sedan. the origional finish was a rubber type of material that looked like it was moulded on to the boards. The bed liner looks great and lets the ribs of the board show. This was done about four years and 50 thousand miles ago. Still looks great and is easy to look after. The guy that did the spraying made the texture so it ended up with a smooth finish compared to some boxes I have seen. Check with a local business and ask if they can "reduce the lumpiness of the material". You will be pleasantly surprised with what can be done. My cost was $100 Canadian.
