just do it right the first time, have hydraulic hoses made. my dually sits for days at a time, doesnt leak a pound of pressure. It is expensive but hydraulic hoses are good to 3500psi and are heat resistant. plus you can use jic fitting and never have a pipe thread leak either. plus using hydraulic you can use bulk head fittings and not have anywhere lines can rub.
On the 88 - 98 Chevy trucks I like to run the lines with a 90 deg fitting & run the lines trough the frame. I like to keep my lines as far away as possable from the exhaust manifolds / headers as I can. I mount the valves under the cab inside the frame C-channel as far forward as possable. This truck has Choppin' Block arms & Slam HE-8s, yeah they are dual ported.