Firestone 2445 ride rite?

Just installed on my Tundra and tow a smallish (6500lbs) 5th wheel with a hitch weight of 1100 lbs. Truck handles it great but decided to add the bags.
Two questions.

-How much air to add and when you should add it. Is it best to add the air before or after you hitch up and should you just add enough air to get back to my stock "ground to fender" height of 39"?
- What do most of you do when the truck would need to be lifted by the frame, simply let the air out? Has anyone had any issues in this regard. I've read about the daystar cradles but don't care for the idea of adding an extra inch of height to the rear. Thanks.

 

I hook up and lower the pinbox until it hits the capture plate and let it sag the truck down an inch or 2 and add air to get stock height. Better to measure from bottom lip of rim rather than ground so tire pressure/sag is not in measurement. I have the cradles so no help about the lift.

 

Ok i'll give that a try, thanks. How do you like the cradles, did you notice them giving the back end to much lift? Also you have the same 2445 kit, just in case I decide to get the cradles want to make sure they fit.

 

At stock height in rear the ride was rough even with only 5lbs air in the bags. The thickness of the cradle was 'preloading' the bags. I lifted my truck right after doing the bags 3"frnt, 1.5"rear which took care of the issue.