So ... just talked with ScubaRX (great guy! ... & his wife was perfectly pleasant too!) ... first, to confirm, my tongue does not have the second bolt (vertical under the LP tanks) ... ScubaRX informs me that the 2nd bolt came into play later around 2016 when someone reported the nut had come loose from the bolt on the main tongue bolt ... only happened once, but in being cautious the Oliver folks began using a 2nd bolt for safety thereafter. Otherwise, Scuba too indicated a small amount of play/rattle is not unheard of. So, again, I think I'm good to go. Thanks all! Cheers