My Roadster is four years newer than yours but the hood may be the same design ? Mine does biillow slightly with both the hood and sidescreens in place, but only over 60-70mph. At what speed do you encounter the billowing ? The hood fabric should be fairly taut and it sounds as if you have tried many adjustments, have you looked at the "slider" on the frame which gives about a one inch fore-aft adjustment ? (You may need to shorten the short arm of an Allen key to gain access).
![[Linked Image]](https://www.tm-img.com/images/2026/08/31/Hood-slider-passenger-side.jpg)
![[Linked Image]](https://www.tm-img.com/images/2026/08/31/Hood-surface-crop-to-show-tautness.jpg)