Japanese to English Tech/Engineering Automotive / Cars & Trucks

This is my first technical project - am trying to find a translation "voice" and stick to it for consistency's sake.

I translated this as "Underbody lip root section and one way section are too close," but was also thinking of something like "Lip root section and one way section of underbody are too close"

I also was wondering whether to use "section" or "portion" for 部、 as I've seen it translated the second way as well.

(American Excel document, English division of Japanese auto client.)

Thanks!