If it was me, I'd either use a Kicker KeyLOC line out converter and amp OR their Kicker Key 500.1 amp, since both with restore all the factory roll-of in an SR+. The SR+ rolls off the bass fast under 60Hz on the front speakers.. without something to flatten it back out, you're missing a lot of sub-bass.I bought the Tesla Offer wire harness with subwires. I am planning to do the same like what you have done already. I have not done this kind of DIY before. How long did it take you to do? Do I need special tools?