I'm sorely embarrassed! Welcome to madness of CHR!! Hope you're getting the responses you hoped for, and that your fuel pump project goes smoothly on the old truck. On the oil since you know that it was not leaking before the new filter, and that you only ran it a minute or two leaking you cannot have put much more than a few tablespoons of gas in the crankcase, if any. It is entirely possible that the fuel smell you're getting is just blowby contamination. Multiple changes of the oil & filter would indeed be safe, but on a bone stock '68 truck and given the cost of oil today I think I would just let it drain until it quits dripping, pre-fill the filter, tighten the plug and fill it up with your favorite oil. About the only place any oil is going to be hiding is in the lifters and maybe a few puddles here & there. If this were my old gray Ford I'd change it once and call it good, but that's just my $0.02. Changing it twice surely cannot hurt anything but your wallet