I have no experience with the Painless setups. It would work, but you'd still have issues with your instrument cluster working half ass. The money you'd spend on that painless harness would probably get you the factory harnesses and a couple more parts in the process! I would say yes, it's worth it to do the swap IF you have a donor car available. Mine was a total loss so it worked out for me this way. I'd much rather have an 03/04 Cobra drivetrain, but we can all wish can't we!