Underfloor lighting: How to fix?

Moin moin, tomorrow I get my underfloor lighting (2x60cm and 2x92cm tubes). But now I don’t know where and how to fix them best to the sides (for front and back I’ve already found possibilities). To the right and left of the underfloor there are brake and/or fuel lines long. I’ve already used more force on the mounts and they are extremely tight. I thought I’d fix the tubes for the side until I came in, once hanged someplaceble I’m thinking about drilling holes through the underbody, which I really don’t like to do, because of rust and gutter. Who can give me tips? Best of all, someone who’s done something like that before.