#1
does turning the truss rod to make my neck shape like U rather than n give me more allowance for a lower action?
#2
what? like a U rather then n? lol

The neck should be as straight as possible
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Faded Gibson SG Special - Black ice mod
Seymour Duncan SH-5 in bridge
B-52 AT 112
Ted Weber Mass100 attenuator
EHX Small Clone
EHX Metal Muff
DIY Modded tubescreamer
Dunlop 535Q Wah
Wax Potting tutorial
#3
yes

A very, very straight neck will let you have the lowest action you can get.

Also, check to make sure that your frets are levelled.