That will all be fine, the trannys I build retain all the function of a stock one. As far as shifting into overdrive under power, it will hold, but you might be better served going with a three disc lockup convertor and locking third gear. That can be achieved in the tune or with a switch to initiate lockup. I currently have a Vigilante 3 disc in mine and will hold all the power I am making with no issue. As a bonus, with a 4.11 in the Camaro in OD and locked up, it will still pull down upper 20s in fuel mileage.