FWIW, here is my technique - which I found very fast and efficient. We'll see if it leaks.
I cleaned the entire skin and ribs and clecoed the whole thing together. Mixed up 2.2 oz of proseal (2.0 of white and 0.2 of black) then "buttered up" two ribs (did 3 one time) and clecoed them in place carefully so as to not disturb the proseal. I only put 4-5 clecoes in each side of the rib, which seemed more than adequate (either the holes line up or they don't! The flanges should be flush if they are prepped OK).
I then put a rivet in every empty hole and shot / bucked them solo. This goes very fast - no need to talk back and forth and confirm position, etc. I had planned on having a helper but schedules sorta dictated otherwise. No problems - the key for the LE rivets is to have the rivet set and bar clean - no proseal to allow things to slip. I didn't even find it necessary to clean off the tip of the rivet before setting it - went fine regardless.
I used the non-swivel set with the rubber guard. I think this is the best compromise for me. Much better rivets than I can get with the swivel set.
I was able to do 3 ribs yesterday in under 2 hours including cleanup. I did not check every rivet after I got the rhythm down - once you get going, you can tell if it is good or not (even when you can't really see the shop head).
This technique worked well for me ... I finished all the interior ribs in 4 sessions, about 8 total hours. This includes the filler necks on both tanks.
All in all, the whole proseal thing is not nearly as bad as I thought - maybe it is good that so many people (not you guys) built it up to be a ninghtmare - I had bad expectations!!
Hope that helps someone. There are lots of ways to do the tanks, and it looks like we're having success with all of them!
Thomas
-8 wings