What is a tank screen

[irl]

I am restoring a 74 fuel tank by completely removing the rubbercoating and recoating it as well as cleaning the inside and buying new parts. What is the tank screen that I see in the exploded view and what does it do. Is is a filter and should it be changed. Also what tool removes that large inset screw at the bottom to take it off.

Thanks.

[vash]

i bought a new drainplug for the fuel tank on my 75. it came with a new screen attached to it. i didnt mess with it to see how it came off. but it pokes into the main body of the fuel tank from the smaller baffle tank inside. so i assume gravity takes the gas from the big tank, drains it thru the screen and lets the filtered gas sit inside the smaller baffled section. taking it off was easy, i went to a hardware store with my new drain plug and simply found a nut that fit. (at the time i didnt have any allens big enough). then i bought a bolt, and double nutted it, and simply cranked it off with my box wrench. did anything i just said make sense? if not pm me. if i had to guess at the size of the allen, i would say 17 or 19 mm.

[irl]

Thanks vash,
From the looks of the plug and screen would you think that this is something I should replace after thirty years. It is was all working fine when I pulled the tank. I guess I'll will use your nut system and see what it looks like when get it out. Thanks for your help.