i'm sure the "brake trick" is familiar to most of you. when spinning one tire on each open differential, give it some brake to transfer power to the wheel that isn't slipping. i have only tried it on my pickup, and it worked pretty well. does this work decently on early 80's k5's? i don't really know if my pickup's abs played a part in it working, but of course, my 82 k5 does not have abs.