5.0 not starting.......

[HISSIN50]

if i were you, i would have pulled codes first. that will point you in the right direction.
does the motor turn over, but not catch, or is it totally dead?
if the former, check for spark. then fuel if you have spark.
if totally dead, check battery, battery cables, and starter solenoid and starter circuit (neutral safety switch, etc). dont forget grounds.

you can get a Probst manual and troubleshoot and check components before you replace them. good luck.