The constantly posted method to get full upgrades in "15" days is good, but to actually get 6,000 feet with full upgrades, follow this simple method. Right after you go off of the jump, set your resistance to 3% and use the rockets to get your speed to 200. When it hits 175, bring it back up to 200. Do this until you run out of fuel. At this point you can simply glide to 6,000. To maximize distance, set your resistance to 0% once your speed reached 100, and when you near the water simply stay above it until you lose all speed. KEEP THIS COMMENT ALIVE, IT WORKS!!! THIS DOES WORK.
(with full upgrades then)
 "Toss the Turtle"){kind=icon}
 "Polygonal Fury"){kind=icon}
 "WhiteboardWar: ChopRaider"){kind=icon}
 "Super Stacker 2"){kind=icon}
 "Cargo Bridge"){kind=icon}
 "Learn to Fly"){kind=icon}
 "Straw Hat Samurai"){kind=icon}
 "Choose your quest"){kind=icon}
 "Pong"){kind=icon}
 "Shoot The Snail"){kind=icon}
 "1 level maze"){kind=icon}
 "Splitter"){kind=icon}