Nice Willie! A pro sharp too! I bought mine in 96, when I was busheling. I have only replaced the cable twice, and of course the dressers. Awesome chain grinder. The only thing I didn't like about it was the weak springs on both feeds, so I found a heavier duty one for the bottom carriage, and added two more to the other side of the top carriage. Add oil to the ports once in a while, keep it brushed off and give an adjustment once in a while, and it will last a long time. There is a knack to square grinding, and I am glad that I learned how to chisel file while busheling, before I bought my grinder. Keep the round grinder and use it to take out gullets. I have a tecomec that I bought from Madsens, that works great for that. Taking them out manually on a square grinder sucks. I was contemplating buying the silvey raker grinder, but they quit making them before I could decide, so I talked my Dad out of his Zigelmeyer...I love that too, and wish I would have had it when I was busheling. If you have any questions about your pro sharp, let me know. Also, I had problems with my bar rail grinder not wanting to run, and let a client of mine look at it. He was a tinkerer, and if I remember right, he drilled a hole somewhere and squirted some oil, and blew it out with compressed air(although they say you are not supposed to)...it has worked fine since.
As far as tree jacks...I am glad I have my set of silvey tree savers, but I also got a sweet deal on them when I was falling timber. I just had madsens rebuild them, and it was spendy! Make sure and run the right oil in them(mobil dte 57). I think that is why mine started leaking. There is a guy making tree jacks now, and here is his page:
https://www.facebook.com/profile.php?id=100005051957860&fref=ts
Look like pretty sweet outfits, although they don't have the capacity that the silvey tree saver set does, they would work fine for most anything anymore. It's been fun talking about grinders and tree jacks

Have a splendid day folks!-