1967 Formula S?? a find or not!

I have a 67 Formuls S convertible, It's a bh27E car and it didn't have disc's or tach from the factory. I bought it new in September of 1967(leftover) in Easton Pa. It does have a 8 3/4 and all the other S cars I've seen from that year do. It was a 273 4bbl with 4 speed and a 3:23 out back.





Today I went to look at a car advertised as an all original, 1967 Barracuda Formula S fastback.
Everything seems to matchup, the VIN tag, the fender tag and it still has its certicard. all the numbers on these match each other .
the numbers also match to the cars options: 273 commando, 4 speed manual, colors inside and out, etc.
It certainly appears to be a formula S car:
273 commando
front sway bar
single resonator cutout in rear valence
emblems
150 mph speedo
8.75 rear ( sure grip)
but two things stuck out as odd for a Formula , firstly it had no tachometer. It has the 150 mph speedo but no tach.
secondly it has drum brakes all the way around.
Could this really be a formula S??? i was under the impression that all formula S cars had discs and tachs.
what gives.
The car is quite beautiful and in great original shape, no rust i could find, very solid straight body , black with a copper interior, 4 speed manual in console, and it looks like very low miles. he wants $14,600 for it, how is that for price.?
thanks, Neal