Neck and String Alignment...

[NovasScootYa]

In order to obtain an equal distance between the E strings and the board edges most setups require a minor neck adjustment. Trying to eyeball it, use a ruler, etc. is somewhat difficult when using one fat string and one skinny string as reference points.  An easier more precise way, especially for DIYers without precision tools, is to replace the fat low E with a used high E string. The high E acts as the low E string center line. In a case where a setup was off on the low side a more precise alignment can give the high E side a bit more real estate and playability.
Also helps with checking bridge string spread and helps with equalizing distance between the nut E slots and board edge.