Plus one for the string method for initial set up. You can use it to find centre lines, check diagonal measurements, wheelbase and set both front and rear wheels to parallel/inline. You struggle with string measuring castor and camber but if you use wheel centers as the point of reference you won't go far wrong. I have gauges to measure camber but not castor (but I think that's fixed on a Beta without adjustable top mounts?) and I have an old optical laser gauge to measure toe in/out too but it's a faff to use. When adjusting toe in/out put a reference mark on the track rod adjustors and keep a note for each corner of how many turns you make so it's easy to return it to the original parallel/square setting if you need to start again. And don't forget to tighten everything up after each adjustment... Once everything is settled down it's worth getting a full check to ensure nothing is wildly out but if the car is handling well you're unlikely to be far out.
Big caveat though - make sure all your suspension bushes are nice and tight as wear in any of them will affect the adjustments!
