Welcome to the forums. As a newbie, the best investment now is to get copies of all the Essential Manuals -see picture. You need the OEM Operator's Manual, the I&T/Clymer FO-4 Manual, the 39-53 MPC, the Ford tractor licensed by Ford parts supplier (they make many exact original parts because the own all the original Ford tooling) and the 8N Service Manual for dealer Mechanics are essential tools to have and read religiously. If you scroll down a bit below, look for the post about an original 2N sediment bulb as I listed a lot of helpful pictures. Here's one with the OEM N-Series gas tank. There is a vent hole on top of that dome so keep it blown out and clear. Don't sweat the petty stuff, and don't pet the sweaty stuff. You have more important things to determine on your new tractor like correct wiring (6V/POS GRN or a 12V switch over job), hydraulic function and not full of water (oil will be a murky brown or whitish color if it is), engine oil, cracks in block, fuel and carb issues, steering, and coolant to name a few.
FORD GAS TANK & CARB:
FORD 8N TRACTOR ESSENTIAL OWNER/OPERATOR/PARTS/SERVICE MANUALS: