My 81 K model has a Kerker full exhaust on it and I was going to put a Dynojet stage 3 in it but I hear everyones nightmares on tuning. Will i be better off removing the plugs and expose the adjusting screws so I can make them richer due to the exhaust and use the stock airbox or go with the K&N ovals and use the kit? The motor is all original with 17K miles. I have all the parts here at the house.