Thanks I will have to dig into that site deeper. That one there is for 55-59 , but hope they have 53.
My filler neck isn't top mounted , it comes straight back towards engine then 90s up with a cap.
Maybe that's the diff from 53 GMC to Chevy ,,, my radiator sets deep into core support and the top is covered , my guess is to make room for the longer GMC engine.
