I never do anything the easy way.

With future plans for MegaSquirt and who knows what else I made provisions for the future.

I drilled two holes behind the washer fluid bottle and used rubber hose as a chafe guard. I stuff the un-used area remaining in the tubes with foam rubber. As I add more wires I have room to grow. Be careful where you drill, the firewall is double wall with soundproofing in between the two surfaces.