The 71 and 72 340 Swingers that never were! (or were they?)
I own the exact car in that picture, plus 2 other '71's and a '72. There is a registry for them.
S/N for the '71's start with LL23H1R. 1972 is LL23H2R. As far as I know the numbers after that are all sequential to the series. Including myself, I believe there are 6 members on here that own at least one year or the other on here as well.