Are you running a ball coupler or a kingpin on the trailer that needs a 5th. wheel? Most ball coupler tubes are adjustable vertically to accommodate different ball heights in the bed.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!