Well, I've put a lot of time in this to get where I am. I have been in contact w/ Hunter Engineering, the co. that makes the most popular alignment machine, and they sent me a conversion table, which I assume is the same as is used by the machine's computer to make the conversion. I also got a neat Excel program from Matt and have been able to reconcile it w/ Hunter's table. Anthony's suggestion: "Call the alignment shop and ask them to convert to inches. I know that the Hunter alignment machines have a table available," has a problem. It turns out that the Hunter table and computer assumes "an industry standard" tire diameter of 28.65", which throws their conversion all off w/ different tire diameters, especially low profile tires. For example, their table shows 1/8" total converts to .25 degrees, (which is exactly what Matt's program calculates when using a tire diam. of 28.65) but Matt's program gives .3 using John's 23.86 diam. I measure the diam. of a mounted, aired Hoosier 225-45-15 at 22.625 and Matt's program converts 1/8" to a tow angle of .633. This is per side so if you wanted a total of 1/8, each side would be .3165, which agrees w/ John's calculation, taking into account the different diam. he used. Does this sound right?

Since I specified 1/16-1/8 total, I should have gotten at least .3165 total but they gave me .07 - quite a bit off.