Post some pictures cause they do help and there's a bunch of guys on here who can help you out. We have fuel cells in our circle track cars but there is no trunk floor and the area is completely open to allow fuel vapours to exit the area. With a street car the trunk area is enclosed so after refuelling maybe a fan can be used to rid the area of fumes. Boats use a fan to get rid of fumes before they start or they have a tendency of blowing up and there are tons of stories on line about that.