A friend has a sweet 57 Bel Air we rebuilt about 30 years ago. Bone stock 283 with a Muncie. He hasn't put a ton of miles on it but is starting to smell fumes in the cab, even after sealing all the floors, shift boot etc.. He's thinking of going PCV but doesn't want to drill valve covers. He asked about extending the road draft tube. I did this years ago on a tired motor, must have been about 16 at the time, don't remember if it worked. Don't want to dig into the engine runs great, no smoke, just this minor annoyance. Thoughts?