I have to agree with the Durabak. I did the inside and outside of my bronco with it. If i remember the course was about 89$ a gallon and you need Xylene to thin it, I found that at Home Depot. As for the gun I got mine from Eastwood company. I used the smooth blue on the outside and it came out better that i thought.
Heres where i got the gun
Heres where i got the bed liner
This is before i cut the rockers and moved the flares higher