Yes, the decals should adhere quite well - of course wait for the future to dry completely. If you do have a surface that is quite irregular you can do one of two things:
apply a 2nd coat of future with a brush and place the decal while the surface is somewhat tacky, or if there is very protruding piece detail where the decal must sit it would be best to just cut out of the decal that area and paint it afterwards.