I should also mention that I am not concerned with seeing behind me; the rear window on this truck is opaque plastic. Speaking of seeing behind me, I should relocate the mirrors inside (they are pretty bad, just by their looks)
Deleting the alternator is feasible (I had a relay on the field control for a while, but noticed no big gains). As a matter of fact, as soon as I swap out the tie rod ends (which should tighten up a bit of the steering slop) I plan to remove the belt to the P/S pump (convenient that there are two belts on the engine, and one of them goes only to the P/S).
I also have an electric fan. When I took off the mechanical one (that had a bad clutch) I could actually feel the difference in the ol' butt-o-meter.
I keep waiting for these stupid 30 inch all terrain tires to wear out, but filling them to their 55 PSI with a 50 PSI sidewall (or 55, not sure) and with their 1900 lb. rating, on a 3500 lb truck... Yeah. They ain't going anywhere soon. I have thought about selling them (They have enough tread) and buying some stock size tires. What are the differences between passenger and LT tires? I wonder what the lowest RR tires would be. Probably something with a very high load rating (for hard rubber. I don't really care about performance traction: it is a truck!).
If I wanted to lower the ride height, I could get some tires below stock size, but I doubt that would help MPG because my engine would be spinning faster at highway speed. I suppose I could make my rear end taller, but I don't really want to rebuild my rear axle until I have to.
Besides, I don't really want to have a "lowrider" or slammed truck
(not to say you were suggesting something that drastic). I think a skirt kit would help (but look kind of silly on a Jeep. Oh well, it's all in the name of efficiency, and I can still load down and haul stuff)
An air dam is another thing I could consider seriously. I would probably weld the supports (although nothing beefy) right onto the frame/bumper. (hmm, that wouldn't be too hard, welding supports onto the bumper and putting skin over it). A grille block is definitely another thing I am open to. My grille is very open to air AND has "bucket" headlights.