When you order, make sure its complete with the two connectors and two push buttons.
Fitment thru the panel hole is perfect so no need to adapt anything. The two push buttons are for changing settings and you need to make two 12 mm holes for them.
After that you connect all the wires, just follow the schematics. Instead of cutting the original wires i made an "adapter" wire so installment can easely be reversed.
Last you set the clock and pulses. Mine is correct at 131 pulses but my setup is very custom so yours might be different.
Some benifits over original:
-Can be adjusted for any alternator/belt setup.
suits 4JHAE better than 5000 rpm.
-LED red light, adjusteble in 10 step brightnes.
-Reseteble trip hour counter.
-Built in clock and volt meter (but wont use that much).