Lisa, the NRCS agent will do the site inspection for the tunnel and handle the application, screening, ranking, and hopefully what will be the contract if you are pre-approved (you outranked other HT applicants).
FSA here does not do anything at the site, just uses aerial photos plus whatever papers you have showing ownership of the land to draw the boundries on their mapping system to create your Farm and Tract. You then will be added to the Producer Report so when the NRCS agent looks that up, it shows that you officially have a Farm and Tract # and that you have control of the land. Other than AGI, I can't think of what else you'd need at this stage other than maybe a w-9 (tax payer id request). Eventually you'll need a direct depost form filled out too.
By all means, sign up as an individual. Much less paperwork.
Everything you mention is correct. You spoke to good agents. I am not sure what else FSA needed.
It's really not that hard for the producer when you see the other side of the process. Just give them what they ask for by the deadline and you'll be golden.
Irrigation is usually for the big guys that are upgrading old pivots, and even then I sense that is very regional specific.
Wells, pumps, and plastic pvc pipes are more common, but every state decides on what the eligible practices are.
We have a micro-irrigation practice that is specific to driplines for hightunnels. It pays less than $200 bucks.
They may not do "irrigation systems", but I would have guessed they'd pay for 1 or 2" pvc to run water from an existing well to a field.
NE has the micro system, but your county might not list it as an eligible practice.
https://efotg.sc.egov.usda.gov/refer...c/NE/NE441.pdf