i have one of those fast track setups. they work pretty good once a guy learns how to use them.
the bungy cord helps to keep them in place, but make sure the cord you use is just long enough to apply some help, and not too short to cause deflection of the aluminum angle the tool is made of.
i bought a magnetic caster/camber tool from speedway motors like the one sniper shown.
as for turn plates, i bought a pair at a swap meet for $20.00. they were complete, but crusty. i disassembled them, cleaned and blasted, then painted and assembled them with new ball bearings. they work great now.
i was lucky the angle indicator labels were still very legible after a thorough cleaning, so i cleared them to keep them that way.
these plates were made by the Wheel-A-Matic Company, Franklin, N.H. USA.
i have no idea how old these may be, as i never bothered to look into this company, or search out any information.
a person can make a couple of turn plates by obtaining a couple [4 in total] of heavy plastic floor tiles, 12"x12", and applying a good coating of grease between them. although kind of messy, i have seen this method used.
for measuring turn degrees, you can use a long straight edge and an angle finder or a plastic degree finder available in most dollar stores.
as with most tools, practice makes perfect. i bought my alignment tools over a time period, so i can't say how much i have in them
i also made some toe plates that bolt to the hub, a couple inches longer than the front tire diameter. these are also able to be used by placing them next to the tire sidewall.
different adapters were also fabricated for different applications as the need[s] arose.
just my experience. your mileage will vary.