There are clearly a ton of factors that go into a front suspension setup, it's way harder thanthe rear setup due to the need to steer as well. To make things really interesting, virtually everything is coupled to something else, in a negative way: push this paramter a bit, something else blows up. It is REALLY a big exercise in compromises, and because you can't have it all, you need to pick your battles. Sounds like you already have a huge headstart in terms of the circle track experience, just learning the lingo takes forever.
A few things to keep in mind, at the forefront, are things like the amount of suspension travel you will be looking at, it'll typically be a lot more than a high speed oval track setup, so insuring things don't go whacky in terms of travel is very, very important. As you noted, the circle track cars can and do run very high camber gains, but in general, this is WAY too much for a road course/street car (by the way, the two are about as closely related in terms of design requirements as there are, if you design for road course, you can detune the setup by softening up rates, etc, and it will almost always work exceedingly well on the street, which is why we take this as a design approach basis for our goodies. It's also the hardest of the suspension "biases" to solve, unfortunately).
I can give general pointers for the priority list, as I see/design things, but I am sure that others might do things differently. You have to start somewhere, or you'll go nuts, the first thing I do is to insure that the lower control arm is parallel to the ground at ride height. At some point you will run into packaging issues, but if you think you can run an 18" lower, that is really good, plenty long enough for a 60" track width. You already figured out that the main thing that affects camber gain is the ratio of the upper arm length to lower, this is also very important in terms of the roll center migration, though not the only contributor. Make the upper, and it's mounting as a start to get the camber gain somewhere around .7 degrees per inch of bump, over the first two inches, and start playing. A suspension program is extremely useful. Alter the upper pickup points up and down, play with the length of the arms, and see how it all affects the roll center height in bump/droop, and also pay very close attention to lateral migration in roll (2 degrees of roll is about all you need to consider). Then you get to start picking your battles.
It's all really complex, as I noted, but it is super cool to play with and learn about. You won't get too much specifics other than general pointers from folks that have it "figured out" because it likley took them a long time to do so, and they will probably be reluctant to share the secrets they found. I know I won't! One dude that di, is Herb Adams, grab his book called Suspension Engineering, it is an easy read, and has a lot of good info in it. Warning, don't copy his front suspension design that is listed in the book, I am not sure if he put it there to throw people off, but it's not terribly impressive and can be greatly improved.
One more point to your specific application, anti-dive. Trucks have a notoriously long polar moment, high center of gravity, and usually have a high front weight bias (static), in braking there is a good amount of weight transfer, exaggerates the whole deal.
Have fun, good luck!
Mark
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