Locking up yak on roadtrip

[Wayne_R]

Thinking about doing a road trip in June to Lees Ferry. Leaving late afternoon and doing a stop at a casino in Mesquite for a night and continuing on next day. Going to have 3 yaks in bed of an open/tailgate down F150. Seeing what any of you do to lock up yaks so no one steals them.

Thought valet, but I will have one yak about 3' beyond end of tailgate. Hate to have some drunk or kid valet run into it and smash it. Doubt we could check it at some sorta luggage hold...guess I could ask, but we have one 12'+ yak and two 9' yaks.

Any ideas? Cable and lock to tie-downs on truck through scupper holes? Thanks for any ideas or what you have done in the past.