my interpretation of what happens in basic terms is as follows:
standard on sprint (or the few that i've seen stripped to that level) is 2 camber shims between the top mount and subframe (not sure about other models).
people commonly fit lowered springs, or regardless, the springs get tired and compress with age anyway so the car sits lower.
as the wheel goes higher up into the arch (just front we're talking here) the camber decreases (becomes more negative), and while aiding grip as the car leans on cornering, even on generally straight roads (the majority of distance covered by the car) the suspension is running lower as when cornering, hence wearing inside of front tyres.
i've rebuit my front end using 3 camber shims each side, and will be on 1" lower springs with adjustable seats, and planned to drop her a bit more too.
im not sure what effect this will have on castor angle, but should be able to compensate when tracking is set up.
sprint should be slightly toe in i believe, have data somewhere... no idea what fwd should be, or if the subframe/geometry is much different to rwd dolly
all a bit trial and error really id say...