I believe we've gotten all of your numbers figured out. There should be a casting number on the head right next to the valve cover on top of the left side toward the front. Given the casting date, though, it has to be a '53 head.
I don't think any of the '54 non-powerglide blocks were prepped for hydraulic lifters (drilling the required oil passages). This wasn't standard practice on all blocks until '58 or so.
I recently bought a whole bunch of patch panels for my truck. The body is as bad as you described yours. For AD's, all the cab parts are identical for all truck series, and many reproduction pieces are available from any of the vendors. As far as any other parts, such as anything for the front clip, there are no new big-truck-specific parts being made. The only option for them is to find good used pieces.
