Hello all I have a late 1967 SV, without seatbelts. This strikes me odd, as I think that was the first year lap belts were mandatory. At any rate, I am looking to add them (lap only). Any guidance as to where the holes in the floor go and/or shouldn't go? No evidence of factory holes exist. Thanks in advance, Bill Mounce 1967 SV aka 'The Paperweight'