Homemade False bottom

i currently am using a 10 gallon rubbermaid cooler with a ss braid and am thinking about trying to make a false bottom instead. i don't feel like spending 40+ bucks on one when i have access to everything i need to make it probably for free. i work for a heating and air conditioning company and we have a sheet metal shop. I'm pretty sure we have some stainless perforated sheets laying around.

i have two questions. what would be the best design for hooking it up to my ball valve? i was thinking about just making a dip tube kinda i guess and having the fb just rest above the ball valve.

and also, would it be a good idea to cut my circle a little small and get some small high temp tubing (1/4"?), cut it lengthwise and wrap it the whole way around it so it works as a gasket to seal the sides nice and also so the stainless doesn't scratch the hell out of my mash tun?

well i just found some pictures that have sorta helped. i guess it looks like it may be better to make the fb sorta cone shaped with an elbow in the middle going down to a dip tube and a barb on top that tubes into my barb i currently have my braid clamped to.

Yes the second plan would be better for a cooler, unless you are going to direct fire the mash, you really don't want more space than you absolutely need under the false bottom.
I like the idea of using some high temp hosing as a bumper to protect the inside of the tun (and prevent channeling on the sides of the mash tun).