Yeah, if you don't have that tool, you're gonna have a HELLUVA time trying to set things. Not impossible, but so difficult as to not be worth saving the $35.

Otherwise you have motion in two axes of freedom, and are only controlling one of those.

I only loosen the 3 bolts BARELY enough to be able to move things. Best is to have a competent helper continuously monitoring the camber while you're under the car adjusting. Same deal with rear ride height adjustment (you ARE scaling/have scaled the car, aren't you???).

I do jack by the trans, yes, and jackstands under the torsion bar ends while adjusting.

Your toe-in is exactly what I use, 1/8" total. That with usually 2.75-3.0 deg rear camber (depending on how much grip I need vs. tire longevity - 2.75 is better for even tire wear, but 3 has a small advantage in cornering grip I think).