My 2 cents based on my bugging experience .
If your trying to toss waterlogged/wind resistant bugs in the 1/0-2/0 range you pretty buch NEED a 8 wt ( or 7 wt w an 8 wt line.) However, if you want to toss smaller (#2) bugs and to bugs with less wind resistance, you can get buy with something in the 6 wt range but your going to need a wf6f ( vs wf5F) line and a wf7F might be better still if the rod will handle it. On this topic, I often overline my bugging rods as this slows down the cast, opens the loop and generally tosses the bug slower but with more consistancy in distance and accuracy once you learn to slow your stroke. As for leaders, short and stout works. Don't go under a 10# tippet for smaller bugs and stay with at least a 12-14# for bigger bugs. The stiffness of the leader is needed to turn over those bugs. When in doubt, 6' of 12-15# Berkly big game mono will get you buy in teh thick stuff.
FWIW, I can think of nothing more satisfying than tossing hamster sized hair bugs at thick cover on a still summer morn/eve. Once you work out the mechanics, its very effective and makes for some great fishing moments!