The arrow should point towards the engine...so you have the MAF correct. The hole on the MAF housing is for a small brass nipple to mount. That will be for the vacuum hose that goes to the valve cover. I capped mine off, and put an breather filter on the valve cover.Thanks Parson. I found the arrow on the MAF - inside the red circle.
The red rectangle is where I put some aluminum duct tape over the hole, as I have a small red air breather for the valve cover.
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