Went to the parts store in my Merc recently. When I got out I saw a streak of oil behind the car on the pavement. I had used a plastic tube for the oil pres gauge that came with the gauge set. Told myself I would put something better on but never did. The plastic completely broke off right at the fitting on the engine. [Olds 350 R code.] If I had't stopped when I did, it would have bled out, maybe before I noticed the pressure drop. I picked up a copper installation kit at adv auto and installed it . Oil pres reading a tad higher. Interesting ! I feel confident using the copper but would like something better. Thought maybe a 1/8 inch braided line to the firewall to a coupler I've in Summit and then a short copper line to the gauge. Any ideas out there?