You will need to replace the belt as it will be too short. Once the bracket is printed, stick it on with a small dot of CA glue or some tape. Mark the four bolt holes and the large rectangle opening in the middle. Drill out the holes and I used a rotary tool to cut out the rectangular hole. I chose to tap the bolt holes and then use a nut as well on the inside to hopefully keep vibration from loosening anything up over time. The idler holder and knob are the same as my X tensioner and are installed the same. Again I would recommend replacing the idler pulley with one that has teeth and a 3mm hole.
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