Hello, this is my second year installing the front blower on my nx4510 hst
It was trial and error the first year as I had no manual, no hints, and no help.
It took me a few hours to get the undercarriage mount attached. The pins only go in from L side (looking from front) What I did this year and now plan to do from now on is set the assembly in garage floor on a piece of staging (6x6) right on the pivot point. I measured from floor to rear pin hole and shimmed it to just below the measurement. Pull tractor over top of it and from the front push down on assembly and slide L or R until the rear pin tube is aligned with the rear holes and put a 2x4” or similar object under to hold it there. Go around to where you can reach under and jockey it until the pin slides through. Next turn wheels to the right for clearance and put a floor Jack under front of assembly and lift until front pin tube is in position and install front pin from L side.
It was a piece of cake. I did it alone in less that 45 min. Good luck