Progress! Who knew! I finally made a decision on the front end and decided to go with the simple radiator/grill gob.
I used a trimmed up biker chain bit and a scratchbuilt fan to put in a bit more detail on the backside of the radiator:
Waaargh! I love to use as much mismatched stuff as possible to give a better impression of looted stuff. Orks are eco-friendly recyclers!
I got some rivet work done as well, along with just a bit more detail: