For the grounding kit to work effectively, it is imperative that all the ground points in the engine bay are as free of rust as humanly possible. Upon doing this, I noticed a significant change in the clarity of my radio & less hesitation when I start the car.
For the exhaust ports, it goes like this.
EJ22E from 1990 to 1995 have dual port like ALL EJ25Ds while the 1996-2001 EJ22E/2 all have single port for the exhaust part of the cylinder head.
If you want to buy an exhaust header that works VERY WELL for TQ & sounds excellent, the EBay UEL header will do. It has to be muscled in a little bit but it is an incredible piece. Good welds, stainless steel, good quality all around. I'd grind away at the inner excess piping for more flow though. Wrap it with heat wrap. It increases the under-hood temperature.
http://i172.photobucket.com/albums/w40/Kenshin1984/The%20new%20car%20of%202011/0804011054.jpg
^ - What the UEL eBay manifold looks like when it's installed.