Yes, it does take some time to get things right.
1.Find out how far your retract need totravel from fully retracted to full extension. The retracts lock in both positions.
2.With retract fully extended install servo and determine approximate length of rod.
3.Connect rod and hit the retract switch. It will not even come close the first time.
4.Now remove servo wheel and hit servo retract switch to return servo to the extended position. Place servo wheel on servo as close to locking in the position as possible and adjust rod length to fine tune.
5.Once you have that taken care of retract the wheel and make sure it locks in retracted position as well. If not you will have to experiment with rod length, servo wheel placement, and possibly make a slight bend in the retract actuator wire. The idea here is to achieve a balance between the two servo positions.
6.Start off with the front retract since it is easiest to access for the multiple adjustments you will be making.
7.Once everything is adjusted properly you can screw in the retracts and servo mounting trays and do not forget to loctite the bolts.
I had to put a slight bend in my front retract actuator wire to get full travel. I think I posted a picture in my build thread. I hope this is helpful.