deck height 6800

[DW]

decided to level and set my deck height this weekend. along with the deck adjustment it looks like the belt would be loose or tight depending on the deck adjustment front to rear. about the only adjustment i see is the threaded part on the front and the two adjusters at the rear. the red knob works on the front panel. not sure what the two threaded ends on the front control. would like to avoid the school of hard knocks this time. thanks.  Denny