Thank you, Riggle! I have a good friend and neighbor who could help me set something like this up. I'll also need something splined to step up from the engine shaft or output (I'm rather mechanically inept) to insert into the pump - or something I can insert into the pump that will fit the engine. I can handle finding that. 5 or 6 HP should easily keep up with turning that pump. I have an old electric motor I used for backslapping my greens mower, I have been mentally stuck on trying to figure out how to use that. I don't think it would keep up.
The sprayer is just on a frame that would not be suitable to support it in my truck bed when full of water. It was not meant for that purpose. I will need to secure it while preserving its normal use: supporting it when I remove it from the tractor. I also had a handy rack welded up that I can hang hose and whatever else I need on it. It helps stabilize the boom too.
I do athletic fields only. Tractor has a small front end loader and turf tires. While it is heavy and somewhat clumsy - like its owner, I suppose - I am able to go anywhere I need to with it without marking or damaging turf. So yes, I spray with the boom from the tractor mounted sprayer. Only time I use hose is odd shaped cut outs such as turf peninsulas around bleachers, concession stands, or scoring towers, or around fences if it is tight. If I can get the last nozzle on the boom within about 8" of fences and keep it there then I do not need the hose. I made it a breakaway type boom just in case. I only spend about 90 minutes a summer on the end of a hose but I spent plenty of time with one earlier in life. As you can imagine, with only 80' if I have to trim fence all the way around a soccer field I am on and off the tractor a lot. It's like being on leash. Football fields are easier with the track border.
Thanks so much for your help. Think this is going on my winter to do list.