"Is it necessary to bypass?" My answer is "it depends". How "much" do you intend to run electrically? If not much more than what the factory ran, then you probably don't need to do the bypass. Like with Vixen, all her wiring is in really good shape. The only thing I have added electrically is
@crackedback's headlight harness upgrade, the aftermarket radio, which has no external amp and all of the interior lights and the trunk light. That's probably gonna be "ALL" I run. It's just something you're gonna have to decide for yourself. There's nothing "wrong" with the factory system, as long as everything is in good shape. If you plan on some real electrical upgrades though, bypassing it might be a good idea. I'm not even running electronic ignition and plan not to, so what I have now electrically is all there is. That's just one old dude's opinion.