Dynojet 424xLC2: Installation Guide - Manual (Page 178)

A P P E N D I X D
Bridge Extension Installation
Above Ground Model 424x/424xLC
2
Automotive Dynamometer Installation Guide
D-6
8 Secure the center mount extension to the extended runner mounts using four 
3/8 x 1/2-inch pan hex bolts.
9 Continue with installing the runner supports, step 4 on page 3-36.
Figure D-5: Secure the Center Mount Extension
A 565 D
center mount extension