Yeah, this is basically what I hear has been the plan all along. It isn't always easy or straightforward using old mills, but it does help reduce capital costs somewhat. The comedown occurs during ramp-up when the old rusty bits fall apart and cost you downtime - this is where your engineers and staff in the mill have to be brainy and forward-thinking (proactive maintenance) and not yokels (reactive maintenance).
Example: Gleneagle Gold
I must say, all concerns aside, GXY is looking fairly damn cheap at mid 50's.
GXY Price at posting:
0.0¢ Sentiment: Buy Disclosure: Not Held