Culligan Aqua Cleer faucet

[DMLenz]

I have a Culligan Aqua Cleer RO undersink unit. I want to change the orientation of the handle on the faucet to be on the left (it's now on the right). I found the instructions online, but the parts diagram doesn't include the locking pin, nor do I see where it is. I'd need to remove it and then replace it when finished. The rest of it looks pretty straightforward. Any suggestions as to how to find it & work with it? Thanks.