Elise Oil pressure gauge wire feed

[Webbo700]

Elise S2 111R

Anybody know the best route where to feed the cables from for a central air vent mounted oil pressure / temp gauge?

I have the gauge set within the central air vent already and powered up utilising feed from the stereo harness. I have the central floor runner removed and have the cables tie wrapped to the loom and all the way until I come to the rear bottle holder at the bulkhead.
Do I need to remove the passenger seat to gain access to feed the wires through some grommet from the cabin to the engine bay? I will also have to lenghen the wires as the gauge clearly wasn't for a mid engined vehicle.
Any input would be appreciated ???