"cold air intake" piping size

i ended up going with the 180 degree dual snorkel set up
(need a 408 call out though)

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so, for the time being i am using the kit supplied flex tubes BUT i want to figure out a way to replace them with steel or aluminum tubes
my question is, where should i draw air from?

the cowl might be add too much of a fuel smell into the car, and make it too loud

the straightest way seems to be right into the fenders?
does that sound like a bad idea with road debris and possibly getting caught in the rain ?

running them to the front might add to the ram air effect but the tube might interfere with some other things mounted to the front

what are you guys' thoughts on this?