I think you will be better off with 30 nozzles, there's not going to be that big of a difference in HP from 30 to 75s maybe 15hp tops and thats with a race tune, not a tow tune. 30s will atomize better and give you more torque since you are using your truck to tow mainly. 190s are pretty big for a pmax or stage 1 so keeping egts in check will take a lot of tuning.