Thanks for all the input, folks!
I'm leaning hard towards seeing how much less I hate my 2F if I fix current leaks, so it isn't pushing me towards a cheaper/easier diesel.
With that in mind, now I'm thinking I should just bite the bullet and go 1HD-T and have my cake and eat it too. I can afford one this fall (~$7k budget is looking like an absolute maximum for 2021), but I can easily swing $15k in parts by 2023, say, if I'm only as poor as I am now by then. If I get a better-paying fellowship for the last couple years of this PhD, it could be 2022 pretty easily.
I'll see if I want to keep my H55 or just get an H150/1, but I figure I'll get most of my money back out of my H55 if I sell it with my (hopefully still fine but tired) 2F and imminently rebuilt split case, so I shouldn't pin too much on holding onto it.
I am a little curious, though:
- If I was going to rebuild an engine mostly myself (plus a couple trips to the machinist to get things surfaced and getting blocks/heads magnafluxed etc.) to get the most possible motor for the money...what would you pick? Fewest fiddly bits? Cylinder liners vs. bare bores, IDI vs. DI, type of injection pump, etc.?