"Worth it", Joe, did you really say that? After reading so many of these discussions with all the help you have provided, I decided "Worth" is an accumulation of lots of things, like:
1. Patience -- at least a ton is required before it's not worth it.
2. Elbow grease -- need more than that 5 gallons needed of kerosene.
3. Money -- no limit helps.
4. Parts -- this requires a number of similar machines because you can't disable any working ones you have.
5. Sincere appreciation of OSMs.
I'd say if you have at least two of the above, your machine is worth saving.
Keep up the good work, Joe!