Enh, you can just do what HumboldtLocal does and run a "Twister" auto-trimmer for most of the work. Hand trimming what you can.
Auto-Trimmers do a pretty good job these days, they leave a very "cone" shaped nug. What is removed will make some great hash.
It is going to take some time though and you are going to need help trimming those 60 plants. I mean, if one person could do an entire plants worth of trimming in 8 hours, then it'd take you two months to trim the harvest! Even if you stagger some earlier indicas and later sativas this is an absolutely tremendous amount of trimming to do, because it might take more like 24 hours of work to finish a single plant (depending on size, harvest yield, and "leafiness."
Honestly, I think you need probably a 2 man team to chop down your trees for hanging, and stripping of the largest (easiest to remove) fan leaves. Then you'll want another 3-4 man team working the trim, operating the auto-trimmer, and packing everything into jars for curing.
In total, it'll probably be 4 weeks from the first plant you chop down to the last leaf you trim with a team and a garden this size. That's working 8 to 12 hour days...
Figure 60 plants is going to harvest you anywhere from 60 to 600 lbs. Really hard to count your eggs before they hatch... But if it takes me a week to POWER through about 1lbs of harvest... you're looking at, at least, 3000 man hours just for trimming. The auto-trimmer will do the work of 5 people... so that can really save you in the end if you cannot get people to help out trimming.
But, that's a long ways away and you shouldn't let a large, and profitable, harvest deter you just because it is going to be more work than you had wanted. More work is a good thing. You know what they say about idle hands.