I have built (with the help of my cousin and his welder) a sprayer. The pump is a roller pump I got from Value bilt (the old central Tractor) they have one that turns the opposite from a regular pto one this one turns the opposite and can turn up to speeds > than 2000 rpm it is ment to go on a gas engine but the shaft is the same as the other so I was able to put the pto adaptor on it. The next problem was the cub shaft is different I had a hard time but found an adaptor to change the cub to the standard pto size and 6 spline. The pump works great plenty of pressure. For the tank I used a 15 gal Cone shaped poly tank I wish it was 25 gals but I had this in the shop. I made a mount that bolts on right ahead of the break pedals sorta like the planter mount. Then we took 2 -- 1 1/4 square tubing about 6 ft tall and stood them up behind the seat with a plate on the bottom to bolt onto the draw bar and two braces that hitch on under the seat one on each side. THen run a 10' boom out the side it does three rows (about 3ft rows or with the cub close to 40") I like to run out one side, I had a tobbacco planter once with a 8 row boom out the side to spray corn I liked it that way as at the end you don't have to get off and move the boom in. Also now I can plant 6 rows of something and never have to go down the row. I plant about 1/2 acre of peas and also 1/2 potatoes and some other vegetables. With the cub in second gear little more than an idle I have 35lbs of pressure and use about 40 gals to the acre. I think I will get different nozzles to cut this back to about 25 gals to the acre. I got my clamps, body nozzles and nozzles from gemplers. If anyone would like a picture I would e mail it to them.
Also the dealer I got the pto adaptor from has one more left, I am not sure if they are that available, I do know the Kubota had the same size pto on the earlier models. One must be careful not to hitch regular pto eq up as the pto turns engine speed and the wrong directions. I think a corn chopper probably would clean the old cubs belly out..