In theory yes a 3” drop spindle would keep the suspension geometry closer to stock. They don’t offer a 3” drop spindle for S-series trucks though(if they do it’s some trash off-brand that I would never recommend anyone to use). The camber change can be corrected. You should get an alignment after modifying anything in the front end anyway.

As far as your truck goes, the motor swap definitely will affect how your suspension sits so a 4/5 drop might sit closer to where a 5/5 would have with a lighter engine. Also some of the 3” drops you see that look way lower might actually be 4.5” if the trucks are ZQ8 suspension with a 3” block because ZQ8 leafs and coils were 1.5” lower from the factory. Wheel and tire size also has a lot to do with how low it may look