I think if you didn't want to mess with the bed height, then you could change the look of the back of the cab with a couple of small raised roll bars behind each seat. Just a thought, but I think it would breakup the line of the tail gate and the back of the cab. Either way lowering the bed, or raising the cab a little will set it off better. I also like Bob's idea of extending the skin on the door, to cover the break in the side. On my 48 truck, they did something very similar, where the door goes all the way down the side on the outside, but is just a thin double wall going past the inner frame for the last few inches.