EXACTLY!!! Get a screwdriver in the hole and take all the slack out of the chain (make sure there is no tension on the driveline... you will get a false reading)best to do it up on jacks in Neutral. Mark the shaft of the screwdriver with your finger against the case and slowly Pull it out until you don't fell the chain resting on the tip. Mark the distance and measure it. I was told 1/2" to 3/4" of play and no more. When I originally did mine... I had 1 1/4" of slop!!!
My new chain after install had less the 1/4". Teh new chain took alot of slop from the drivetrain.
78 Wagoneer "River Beast"
Dana 44's w/ 3.54's (soon to be 4.88's)
7" SOA conversion
4" Skyjacker Softride
3" Trailmaster Bodylift
33x12.50's on 15x10's
(soon 38.5x14.50's on 12's)
My FSJ site: http://www.geocities.com/~spazz4life
"Where there's a hill...there's a way!"