I have been working on cars for years but have always taken my my cars in for "perfect alighnment". I would like to know if there is a tool or a measuring way to correct the alignment.
Sure there is -- it ain't rocket science and you've already dealt with the Goobers at the alignment shop, so you know it must be true. I use Longacre's caster/camber gauge and toe gauge. http://www.longacreracing.com/catalog/item.asp?id=129&catid=5 I stole a trick from a Mazda Miata guy, and stack two 12x12 linoleum floor tiles with a shot of grease between them to use as turning plates under the front wheels. That way you can turn the wheels through the 20 degree arc you need to measure caster, by hand. I also went real far out, and figured out how many I need at each corner, so that the car is perfectly level in my driveway. I bounce the car up and down then roll it by hand onto the tiles. On a Mustang you obviously need caster camber plates for any adjustability (I have old Steeda's), but I've also done my Chevy with the ancient GM shim setup. Takes me a long time though, usually an afternoon. And on a fresh job after parts replacement I usually have to go back under to tweek it the following week, just to dial it in some more. But like you I gave up on finding shop that would do anything but a "factory" alignment, no matter how much I paid or tried to work with them. It's been about five years since I started doing it myself and to date all my cars drive straight, have decent feel, and show normal tire wear. Plus I get great satisfaction knowing what's happening under there, understanding it, and being able to tweek it.
Thats pretty cool. A homemade kit. The shop I work at, our alignment guy really does a great job. When someone comes in with thier own specs, no problem, but no warranty if it pulls or something.