I dont know how you get away with a 6" lift and not a SYE to begin with, but thats what you
need, seriously, get the trans/trans back up under the body where it belongs, about the easiest way to do this in your case is to do the 1.25" bodlylift so you can do the 1" motor mount lift. I am a huge fan of RC, they have everything you need.
When you start getting above 3 or 4 inches of lift, you cant just throw the lift kit on it and call it done, and at 6" I seriously hope you are also paying extremely close attention to your trac-bar / draglink angles as well, if not, your about to have an accident.
I would also recomend you reading the "tech info" section of
http://tomwoodscustomdrivelines.com/
edit: after looking at the kit I'm glad to see the drop pitman arm and drop trac-bar, but seriously you need the SYE, you can get them on e-bay complete with driveline for about $410, its an Advanced Adapters SYE kit and a custom CV shaft made by a place in SLC thats very good, but you need to contact them ahead of ordering to let them know your on a 6" lift.