Yup. I have the circuit isolated, it's just a matter of time allocation at this point.
I believe (and it was pretty hard to see out there in the dark last night) that the fuse is actually in tact, so it's possible the previous fuse wasn't up to the task and something burned up... Alternatively, it's common to have the switch itself acting as a fuse of sorts, though I think if it were tripped at that level the associated elements (headlights) wouldn't function so I'm probably safe there. I did notice when replacing the previously burned out tail light bulb that the housings have been underwater for a time. If I'm to start cleaning grounds, that's my beachhead. I'll get out there later today (time permitting) and check out what on the circuit is good and what's bad, and probably clean the tail light housings up a bit and see if it helps.
Meanwhile, I noticed yesterday that at about 65mph the back end starts to shimmy as if it's either out of alignment (which I don't think is really an option on these, but I haven't looked into it too deeply yet) or the tires are out of balance... Gotta get that fixed.
Additionally, there's the rattle in the transfer case linkage that needs to be tightened/adjusted out.
There's a weird noise at idle. I think (and this is my aircooled ignorance showing) it sounds like a bubble or something in a coolant coolant line somewhere close to the firewall possibly associated with the cabin heat. Really not something I'm familiar with.
I also noticed a noise at idle that I have traced to a bearing (front if my ears are still any good) in the input shaft... The best way I can think to describe it is like a large ball bearing (the sort one finds in a transmission like this) that's a bit loose (which is exactly what it is, but the default bearing sound is a whine). It goes away if I push the shifter into the 2nd gear synchro (hence input shaft). I need to check the fluid level.
At some point also, I need to adjust the steering box and the drag link to tighten and recenter the steering wheel....
Finally, I want to get with Ricardo soon to get the carb dialed in. It's very difficult (read: I'm not that good) to tune a carb by ear in a car in which one has never experienced a proper tune. Even then, that hunk o' cast iron is probably pretty tired... Rings and a head job may be in my future over the coming months, it's really hard to tell with no baseline experience.
The list is stacking up! Meanwhile, things with my company are finally picking up, so my ability to tear through projects is rapidly diminishing. I spent all day yesterday getting the exhaust and windshield handled, and I have some catching up to do...
EDIT (Steve posted while I was posting): The fuse block is really clean. There's actually not a lot of rust on the truck and the wiring is, on the whole, in really good shape (it's on my pre-purchase inspection checklist).
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