There are marks on the gears....on stock gears... the cam gear usually has a dot...on the crank gear.. stock has a dot too... on upgrade gears.. the cam should have a dot.. the crank will have numbers...-2, -4, -6, -8, 0, +2, +4, +6, +8...with a keyway slot on each number. Best thing is what I think you said you did...line up the marks before taking the gears off.. the cam gear dot at the very bottom at 6:00the crank gear at the top at 12:00...take them off.. slip the new ones on..dont move anything until the chain is on and the gears have slid on the keyways.. tighten the cam gear...torque it...

 

Well I didn't line them up, as I noticed they were keyed. I can understand it's best to find out the slack and all for the 6 and 12 lining up, I just couldn't get it to crank by hand. IDK if your spose to remove the spark plugs or what, so I just decided that it'd be ok as long I slid them on the keys without moving anything. Also, I couldn't torque it, so we used the air drive to tighten it, and then marked a line and tightened it just about 4-5 mm past that. You can't torque it with a wrench because it will move around, unless you use the screwdriver method which I didn't.