</font><font color="blue" class="small">( If the hydraulics on that tractor work today, they'll probably still be working in 10 years. If they are poor, that could mean a lot of expense )</font>
Not as bad as you would think. Just this afternoon, I completely rebuilt the hyds in my 52 8n. That included dropping thr pump and resealing it.. addin a new relief and check valve, and also pulling the hydraulic top cover, changing out the 3 steel ring piston with a newer o-ring style NAA piston, resealing the hyd cylinder, and replacing the cam folower pin. Parts came to about 70$ including shipping. The only thing I didn't replace was the cylinder itself.. That would have been another 85 bucks. I was able to hone mine with a brake hone.. Most can be honed unless they are completely gutted. The NAA oring is much more forgiving with cylinder ID than the steel ring/piston setup.. It is an all day job.. anbd is easier with a helper.. even if that helper is a wife, kid or neighbors kid.. but it is completely doable by yourself with no more than a torque wrench, 11/16 box wrench, and socket and breaker bar, and a razor blade to scrape the gasket flanges. A bottle jack helps you hold and position the 50# belly pump while you finagle the control valve into place. The topcover weights about 80# and is a bear to manhandle.. but again.. I did mine today.. Mostly labor and lots of oil/greasy grime.
Soundguy