DIY Wheel Tracking Tool

ok this is how i do the tracking, above you can see a long bit of alloy angle, (from an old patio door i think!) either end has a right angle upright with movable prongy bits attached to each upright...

you slide the tool under the car and line up the prong half way up the wheel, this side has a prong that moves in and out.. you do the rear of the wheel first usually
This side has a prong that can swing so you can get it up to the wheel rim, you but this side to the rim first then move the prong on the other side up to the rim ,You then carefully slide the tool out from the car making sure you dont knock the prong that moves in and out, then do the same on the front, lining up the in and out prong first.

Then on the side with the swinging prong you use a feeler gauge to see what your toe in is. If its toe out the swinging prong will touch the rimhope that makes sence!