Im fast leaning in that direction, i may just wait and buy the tachulator, its off the shelf, programmable, it comes with the sensor, and it has good reviews, I did'nt want to go down the build your own route as ive done all this PCB DIY before it drives me nuts but at least i had a go. the thing is i dont enough hours in the day as it is. Having built the circuit got the display and the sensor now comes all the tinering about, it really would have been quicker and less hastle to just buy one lol. but i really do believe in buying within the UK if possible..