Regarding Trico bottle tops, here are some other examples I've found. The first two are from 428Street - the second being his ERA - hope he doesn't mind my posting.
On these websites are more photos but they are protected from copying:
1967 Shelby Cobra 427 This is CSX 3357 and has the fill port at right rear and suction tube in the center.
1966 Used Shelby Cobra 427 at Canepa Serving Scotts Valley, IID 6863033 This is CSX 3112 and has the filler at left-front and suction tube in the center.
No telling how many of these are original but there seems to be a variant with the fill port at the firewall (right-rear) but most have the fill port at the left-forward corner. Some have the suction tube dead center of the cap and others have it in the right-rear corner. Very inconsistent
Maybe Nick can shed some light on all of these variations.