Evening Chad,
I haven't answered your pm because you have gotten some really good advice by others.
A block and tackle is a minimum of two pulleys connected with rope. It's kinda sorta like a gear reduction assembly for manual work.
Gin poles are poles used by themselves or with others to hold a pulley or eye for the purpose of lifting materials.
After reading some of the replies to your post I've decided block and tackle with gin poles would be sending a D7 to clear snow off the drive. Based upon what some of the experienced carpenter types here have said the twenty four foot trusses are just about right for a couple of guys to handle.
I probably sound more than a little prententious but as has already been said, you need some experienced help if you can't get more help.
There are lots of ways to do what you're wanting to do safely. And even more ways to do it unsafely.
If you and your bud are inexperienced with working on top of a wall then I strongly suggest you figure on making or borrowing, but using scaffolding.
The trusses are awkward to handle, wanna twist and flip for no better reason than they can. That is multiplied many times over when you're up high and trying to hold on with one hand while working with the other two. If you're handicapped like most of us and have only two hands to start off with it's even more difficult.
If your bud is slower or faster than you and you've not done much together then you've got a whole nother basket of problems.
It would be terrible if you took my advice and attempted to do something the way I've suggested and ended up permanently crippled. That's why I've turned so negative on this subject.
It's a dangerous project for experienced folks. It's extremely dangerous for the rest of us.
You will do this thing. And if your TBN friends have done their best to help you out you will find a way to do it safely and we'll all be proud of you and ourselves.
We expect pictures.