Wow Gunther, it sounds like a fun time in the basement. Just in time for 
winter you can have a VAX running to heat the house :-)

My experience with Qbus VAXen is that the TK70 lights blink/extinguish 
cycle is a motion error on the tape. That occurred when the TK70 thought 
the tape had stopped moving because its idler cam sensors were dirty. On 
one I fixed it by blowing "dust off" between the sensors, on another I 
think I'm going to be stuck taking it apart and cleaning/reassembing it. If 
the LED is dead then I'll have to fix that as well.

Probably the simplest solution for you would be to have another VAX running 
VMS and then cluster in the 6000. That way you could boot VMS from the 
cluster partner, use the partners media etc. That requires only that the 
ethernet, CPU, and memory are working on a Qbus VAX, I don't know about a 6000.

--Chuck