Durango shops, 1970s

All this talk about the last shopwork done in Alamosa got me to thinking about the 1970s and the shops in Durango or lack therof.
Could the shops do any and all necessary work on the locos? Was there a drop pit? It must've been cramped in that old roundhouse, not designed for major work.
I know that three stalls were where the machinery was, but how much could they actually do with what they had, and what did they have?
The 481 and 497 had parts borrowed from them during the 70s, were these two locos parked where the torn down stalls were?
How much and what types of equipment were brought in after Bradshaw took over?
I remember it cost $2 million to build the new roundhouse shops in 1989-90, sounds like a steal now.
Thanks