Had a conversation with one of your sales rep in one of the forums. Am going for stage 1 mod. SE air filter, EJK with O2 sensors, 2into1 ( didn't settle my mind whether Rinehart or D&D fat cat). Might wait a little on the exhaust for cash flow issues. Shall it be a problem if I install it on the stock pipe or I'd rather wait for a complete mod installation?