Sorry about that. Just had a look at those instructions, interesting way to do it.
As far as using the FEL, what Bobcat installs is a 3rd function. However, they use a diverter valve and divert oil from the 3 Point hitch (and backhoe if installed). Since it is not likely that you would be opening/closing the grapple at the same time as raising/lowering the 3 point hitch, it’s a slick way to do it. Don’t know if it’s common with other manufacturers as I’m too new to tractors.
Interesting that aftermarket companies don’t take this approach.