Hello! Heed me op, got your fix right here. There's a goofy filler neck that comes off sometimes, a couple people have marked where it's supposed to be with red squares. It's gone though! There will be a hole in the top/side of the valve cover there with lord knows what field expedient solution plugging it. ~Mine~ was a chunk of radiator hose that came up to the original location with the original cap jammed back in it to retain convenient access, but we can't all be the world's greatest shadetree mechanic. Here's a video of some nerd actually fixing it with factory parts like a big dumb loser with way more money than me, just to help you find it:

https://m.youtube.com/watch?v=FNaJr_PD97g