Apexi Rsm Gp

[240k convertible]

Is anyone using the rsm gp?

http://apexi-usa.com/products/?id=5352&rsku=0

I want to use one in the convertible but I can't find out if they can be run with out an ecu. All I have is two wires coming from the gearbox and one wire from the msd box (for tacho), does anyone know if this will work?

What I'm trying to do is get a speedo and tacho with out spending heaps on a autometer set up. All the other functions of the rsm really make me want it over two gagues.

I'm open to any other ideas that you might have.

Cheers Andrew