So i recently wired up some pointy clocks to my curvy and all works great. The only things i had issues with was the fuel light and the rev counter needle bouncing all over the place, apparently both common issues when doing this.
I have sorted the fuel light out with a couple of resistors with works spot on as it should.
I also have signal filter for the rev counter. This has been tested and works perfectly.
Tacho Signal Filter
I do have the wiring diagram for the circuit if you wish to build your own.
Tacho Signal Filter Wiring Diagram
Hope this helps someone out