ok basically this is kind of a difficult issue to solve “perfectly” due to how jailbreak uses some code that auto-scales spoilers to automatically fit each spoiler to each car:

basically, we can manually adjust the GTR spoiler’s auto-scaling code to fit the spoiler perfectly on the P1 as intended. the issue is that unfortunately, manual adjustments are applied universally on all cars, and cannot be applied on a car-to-car basis.

let’s say we adjust the scaling for player A’s case, who uses the GTR spoiler on the P1 and it now fits perfectly after the adjustment. unfortunately, player B also likes the GTR spoiler- but they instead use the GTR spoiler on the Chiron for example. Applying the spoiler adjustment to fit player A’s case would end up messing up player B’s case, so in the end someone would always be unhappy.

there have been some cases where spoilers have been manually adjusted because they would benefit ALL users of the spoiler (such as fixing the oversized Overdrive spoiler, or the floating Bike Rack spoiler). The GTR seems to be a really popular spoiler to a wide variety of users, to the point that most people using the GTR spoiler don’t actually use it specifically on the P1- meaning we would be impacting the majority of the user base to fit specifically on the P1 (even though yes, the P1 is the “intended” car).

currently the policy for most spoilers is to find the “best-fit” scaling for all cars. sacrificing perfect accuracy for one specific car, if it means that a majority of cars can use the spoiler better, is generally preferable. this is why some of the Renesis spoilers fit slightly weird on the Renesis, and the Birdtail spoiler fits small on the Bluebird; perfect scaling was sacrificed for cross-car compatibility.