Split charge rely through fire wall

[Leew8]

Good morning. I’m trying to fit a split charge relay through from the cab to the battery and struggling to find a way though the fire wall. Has anyone got any tips or ideas?. 
Thank you

[clarkydnb]

Find the main wiring loom gromet that passes through the firewall and carefully push a cable insertion tool through it to put your power cable through or drill your own hole in a suitable place and put a cable gland in it

[Sol]

There's a massive hole where the LHD steering column would have been, with a huge rubber bung in it. Surely you can find that. Passenger side, floor level under the glove box.