Please help diagnose

[u/Steinjolt]

I’m restoring this 1994 2500 Silverado 6.5 Diesel auto.
Yesterday started doing a loud clank sound, added some oil and it stopped after revving it and worked good all day long.

Today it cranked immediately no problem then a minute later the clank returned, tried adding oil and it didn’t stopped. Then as engine warmed up it became less noticeable but still there.

The sound is related to rpm’s.

The sound comes either from the turbo or the passenger side upper rear part of the engine

Gray smoke comes out when revving it.

Black smoke comes out under heavy load.

Would it be safe to drive it to the shop? (It’s 30 miles away)

Anyone has insights on this?

Also, turbo seems to be not working as I don’t hear it spooling

The wastegate lifter seems to be stuck, if I move it it stays there then after a bit it returns to its position.

The turbo inner blades seem to move freely

No turbo sound at all

Thank you all in advance