This is a long story of my E34. Back in 2006 I started a thread on common oil leak sources.
I didn't have much luck in stemming the tide of multiple leaks. Unfortunately this was a harbinger of the worst kind. I took the E34 from Fresno to SoCal for a Disneyland trip in 2009 and I made a fatal mistake in not regularly checking the oil level.
It went off song on the way back and I feared the worst.

Took it to a shop and they said HG, maybe worse. I said hang tight. Put it in the RV space in my side yard uncertain what I'd do with it and bought an E60. Shared my pain here.

Thought it was a HG so did a bunch of reading, Pelican Parts, etc and convinced myself I could do the HG in my spare time. Deep breath. Dug into it. Horrible realization.
1800 views and public discussion that the OP was the killer of this car. Aaaaagh.

I can't believe it. How could I be so stupid? Now I'm way into this car, it's in a zillion pieces. I'm responsible, I can't give it to charity like this. Holy crap! What now?
Well, I guess I need to throw a short block at it.
...and yank the motor

So, so far I've pulled the head all apart (Pelican cam method) cleaned up the very heavy carbon deposits, cleaned the valves spinning them in the lathe took it to a machine shop for flat check, it passed.

Lapped all 24 valves, leaked checked valves. Put solvent in CCs and blew compressed air in the ports.

Some leaked.

Re-lapped leakers, reassembled it.

Set the head aside and pulled the CraigsList shortblock apart. Will do rings and bearings. Got the hots to "freshen up" the tranny so I enlisted the help of a friend and bought an ATSG manual, a TranStar kit and several gallons of Simple Green Max and got busy. 178k miles, tranny probably needs a refresh right? Grubby before photos.

Man there are a lot of parts in a 4L30E. Like 600. The internals looked brand new, the clutches are pristine, the seals a bit hard. Did find a broken belleville spring in the overrun clutch but nothing else. Cleaned it and reassembled in about a week of evenings and a few weekend day sessions. Tedious, particularly since I didn't buy the several hundred dollars of tools, improvising with my lathe, press and assortment of aluminum stock. Made a conical seal installer and the pump alignment tool on the lathe. And tons of time in the parts cleaner. Air checked all the clutch packs, double checked end play, pin bore clearance etc.
Cases (it has a separate overdrive case in front of the main case.)

4L30E is finished! Looking forward to installing it.

Working the shortblock now. Don't like much of the CraigsList shortblock, may only end up using the block and caps and use everything else from mine. The front cover is corroded, the plunger in the oil pump is scored etc...
More updates to come.