The people I bought my 914 from in 75 had 2 kids & removed the center console to make it more comfy for them to ride there.
On several occasions I'd driven with 3 across the front - me & 2 gals usually in my single days, a couple of times with 3 of us Ruggers on the way to the 3rd half - or from it!
... also drove with 6 inside & top on thru the burger drive thru!
That cop who was the supposed PCA prez was full of
& probably never saw inside of a 914, let alone knew the specs.
Sir Andy, my 8/72 built 73 2L has the extra threaded receivers for the 3rd belt, but the gas tank sticker says 2 passenger (not 2+1), probably because the "included option" center console on the 73 2L's made it impossible to use it for a 3rd adult due to the lack of leg room.
Here's why it needs to be a 2+1 when you're driving along (reverse the idea for our female Teeners) -
Click to view attachment.