Outer Limits 4x4 Board

I had three electrical gauges fail on me in eight years, so I am changing to a mechanical oil pressure gauge.
I bought a Speco gauge that came with some nylon line, I wasn't to keen on the nylon with the high under bonnet temperatures and off road use .
They also had copper line which I have run from the gauge through the fire wall along the top of the chassis rail and then into the port,put some split hose over any sharp bits and cable tied it down.
What i'm concerned about is the movement from the engine weakening the line, it's fixed to the chassis near the engine mount and has about 100 mm of free length untill it atatches to the port.
The engine moves quite a bit on the engine mounts, they are v12 jag ones and only 18 months old.
Will the copper cope with this amount of movement or should I convert it to nylon for the last 100mm or some thing even more flexible.
Any thoughts.
Regards Michael.

I have run plastic line from my 318 for 11 years and never had a problem with it..

I went to Enzed and got an adaptor to run 150 mm of flexible rubber tube from the engine to the chassis rail where the copper then connects.
Primed up, and with revs the rubber is working well.

Given time the copper wil work harden and break.

I run the nylon line off my manifold for aboost gauge and it seems happy enough.