The tracks were changed out at some point, I do not know what the "new" tracks are from. All the parts are mild steal and every 5th one was a double stack of square tubing (picture is a single). The original belting was too short and was extended to fit this machine. Most of the wheel guilds are welded permanently like the part on top. When I got done every 4th one is now a double, which go straight across with a small welded pad in the middle.
I have a machine shop in Sheridan, WY that says they will make a mold to make more of the wheel guides as I have been unable to locate any this size available anywhere. I can tell you from experience changing the belting on these tracks is really hard work. There are 64 grousers on each track 10 bolts in each for a total of 640 bolts per tracks.