Thanks J for the kind words and offer of help getting the old gal serviced. I'm pleased that you have a good opinion of the 158 as I'd started to form the opinion that pin-levers were the poor cousins of the escapement world.
In an earlier post of mine I mentioned a movement from a job lot that came out of the package ticking. That was a BFG too and it impressed me by its willingness to run. It had been wound within an inch of its life and to begin with would run for a while, then stop. I twirled it each time and after a few stops and starts it loosened up and ran for about 36 hours.
Bearing in mind that my sole experience of servicing watches has, so far, been in the diassembling side of things, and I'm not yet equipped with a dedicated work bench where I can leave stuff, the proposed service of this and numerous other watches will happen at some indeterminate time in the future. Still, you're young! You'll probably be running the hospital by then!
;-)