Hey guys I have a de-resonated 2011 E90 and I'm looking to do a custom exhaust set up to be more cost efficient. What I have in mind is: replacing my primary cats with Macht Schnell test pipes and removing my secondary cats. I wanted to see if anyone has connections with someone or a shop that can build me a custom x pipe with muffler. After the exhaust mods I want to purchase a pulley kit and do a BPM tune. Please share any suggestions/comments! Thank you in advance!