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Weld the middle spacer (#4) to the rack extension following the spacer welding section in Rack Extension Welding Jig ..
Mark how far the spacer sticks out from the tube, the spacer should be as centered as possible in the hole, this is 12.5mm from the centerline of the tube to the flat of the spacer. Then give assembly to the welder.
Slide on the left rack mount (#3, config 2), place the mount approximately in the middle of the two spacer holes.
Weld on the left spacer (#4) following the spacer welding portion of Rack Extension Welding Jig againby repeating step 1.
Slide on 2x #5 and 1x #3, config 1 in the correct order on the right side of the rack extension. Where the components sit do not matter currently, make sure all three components sit within between the middle spacer (#4) and the rightmost steering stop (#5) hole.
Weld the clevis (#2) onto the right side following the clevis welding section of the Rack Extension Welding Jig #1. No jig is required the tube and clevis is slide fit and the flat face of the tube sits onto the flat surface of the mating hole on the clevis.
Fix the steering stops to their respective mounting holes using #6 and #7.
Done
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