Rear wheelbase conversion to 12.8 inches

Installation notes

• The 42018 pack contains two 121 mm upper links, two 127 mm lower links and one 75 mm male driveshaft section. Stock Trailrunner rear links are 108 mm upper / 114 mm lower, with a 60 mm male driveshaft.
• Reuse eight serviceable rod ends and pivot balls from the four original rear links. Reuse the existing CVA joints, pins and 33/42 mm female shaft sections where serviceable; install the supplied 75 mm male and keep shaft phasing correct.
• Set matching left/right link lengths and preserve rod-end orientation. Check driveshaft overlap and bottoming at full compression, droop and articulation before running.
• Keep the complete IFS front module and front links. A longer rear axle position requires wheel-arch/body/bumper clearance checks; the kit alone does not prove that any particular longer body is a direct fit.
• The Knightrunner already has a 12.8-inch wheelbase. Builder Kit 3 includes both 12.3- and 12.8-inch link choices, so those setups do not require another 42018 pack.

Sources