Get rid of your stock air box for good!
Stock airbox alternative Right and left side air manifolds bend around rear shock to allow proper mounting of clamp-on air filtersFits 2" universal air filters (K&N, UNI, etc) Filters used with my setup: Uni High-Flow Street Bike Filters - 1 7/8in to 2 1/16in, 50-52mm PK-82Manifold slides over and snaps onto existing carb opening A single automotive hose clamp secures carb and manifold together, may use heat shrink or other thin sealing material between clamp and carb/manifold.I use a steel cable restraint around filter connection area to prevent loss in case of intake knock-off during xtreme maneuvers. (Other end bolted to bike frame)XL600 Intake / Carb boot replacement / Intake boothttps://youtu.be/jRWHg2pFohY
The units of the file are in inches not mm. You just need to scale the models up. Look at the overall length in your 3d print software and convert to inches on google and you'll be good! Use the overall length of the model to scale: example if it is 6 units: 6in to mm = 152.4mm and make sure that you keep the aspect ratio locked and your printer program should scale it appropriately.