1999 f-150 torsion bar question

i recently bought a 99 f-150 4wd. i wanna lift the front end a little bit by turning the tortion keys, but i dont know if theyve already been turned, and i dont wanna turn them too much... help?

Torsion bars are for adjusting front chassis ride height. It is measured/adjusted on a perfectly level surface, front to rear and side to side, (typically found on an alignment rack). There is a specification that they must be adjusted within. If adjusted too high or too low, rapid excessive wear to front suspension parts, steering linkage and CV joints will occur. Best to leave it to the alignment shop.

thanks