Thanks for the feedback, folks.
The engine has 148 on it, and it still runs, with an extremely prevalent knocking. So is it dead? Not the venerable 4.0. Its innards haven't been reduced to nearly enough metal fragments to cause it to stop running.
I haven't heard anything from my mechanic since the last time I talked to him. I just got off the phone with the shop and found out he's on vacation this week. That's just great. This is a small-town garage whose primary bread-and-butter is service to general wear-and-tear items. I trust them, but I don't think they are the right folks for this job. I told them that I'd be picking it up tonight to take it elsewhere for a second opinion.
That being said, I'm not convinced that the engine needs replaced. I wasn't given an exact diagnosis, just - "It sounds like something is going on in the engine. That'll be $4600, please." - Obviously, rebuilding it or replacing it is a silver-bullet; a sure-fire fix, if you will.
I've been networking with friends, and was referred to someone who should be able to help me out, so I'm going to go that route. I'm not convinced that its kaput... yet. I don't think I should drive it at all, though, or it will be.
I'm still pretty bummed. It's warming up outside, and I've been waiting all winter to hit the trail. This past weekend, I disassembled and repainted my Hi-Lift jack, and added stickers to my fridge. How sad is that?
There it sits.
Aww yeah. Pimpin'. This fridge makes it look like I 'wheel.
Much-needed rejuvenation for this old Hi-Lift. Makes it look like I don't 'wheel.
At least I have this pudding cup.