Sorry haven't had a chance to update yet because not a lot of progress just yet but I'll post what I have done:
Gas tank was very rusted and this was my initial cleaning using a pressure washer and mineral spirits. I ended up purchasing POR-15's fuel tank repair kit that comes with everything needed to clean and seal the tank. Haven't had a chance to do it yet but I will post some pictures when I do!
I ended up finding a used sending unit with a broken float assembly for only $50! Just cleaned my original float and level sensor because it works, and bolted it to this one, as well as a brand new Walbro 255lph fuel pump. Just need to drop it in once the tank is clean.
I also fixed the starting issue that it had (the notorious interlock relay failed) and installed Altima e-fans again since I'm much more knowledgeable on electronics nowadays. Lastly, I accidentally cracked my coolant overflow tank so I installed an aluminum tank since it was a fairly cheap "upgrade"
She's coming along, but we all know how these things go haha.