difficulty mounting the midmower on Kubota bx 2370

[kubota33]

I struggled with rear link since it refuse to lower itself to adjust the L pin.I did everything by book with lowering hydraulic control lever to zero inch position for the cutting height, but no avail. What could takes merely few minutes of mounting has turned into a couple hours that I gave up, it has become a nightmare for me. Any advices will be greatly appreciated.