[SLESTAK75]

Matching the ports is not very hard. For the exhaust. When I removed mine I noticed that the hole in the flange where it mounts to the head was smaller than the inside of the exhaust pipe. I just opened it to match the inside of the pipe. You have to do it off the engine so no shavings in the engine. I used stone grinders from the hardware store. They were 2 dollars each, fit in a drill, and it took 3-4 per part. I used a flat sided rounded point for the exhaust and sphere for the intake. For the intake you remove the carb and unbolt the intake. Feel around inside and note where the lip is and then remove the intake and spacer and grind them until they match. An easier way would be to match the spacer first (grinding off of the engine and putting it back only to measure progress) then once you have it matched to the port use it to match the intake. The sphere works really good to open up the inside angle on the intake. Once you have the intake port matched you open up the angle to match both ends of the intake. You will see and feel when this is right. You don't want any narrow points inside the intake. You also do not want to smooth the inside of the intake with sandpaper. Leave it rough. Or you could buy a 30mm intake. This of coarse would cost more money and would mis match slightly larger but better than restriction. Matched is best though.