VAUXHALL ASTRA MERIT 1.4 1995 M REG

Hi there, could you please tell me if the dash clocks out of a vauxhall astra 1.6 / 2.0 will go into my 1.4 astra merit. There is no rev counter on the clocks I have, and there is on the 1.6/2.0. So just woundering if connecttions are the same and would I be able to wire up rev counter. The reason I am changing clocks is because when I drive along at 30, my speedo says 40, and I drive along at 60, my speedo says 70, it is 10mph out. I can only think the clocks are dodgy as put new speedo cable in and still reading 10mph out.
Cheers
Andy