it's there and it does the job, and it does have the period look, so I'd keep it.
Fitted the exact same rev counter in my first Mini, back in 1979. 8)
IMHO if I wanted a rev counter in an early Marina, I'd track down a 3-dial dash with the factory rev counter. My old Marina Coupe had the 3-dial dash (but with a clock), so I replaced the clock with the factory rev counter.
