OK. There are plenty of helpful youtube videos on carb cleaning - disassemble a part at a time and be liberal with the carb cleaner. Is the carb pump diaphragm feel flexible not crispy?
Check the impulse line, this is often overlooked.
Diagnosis is always difficult but personally, a saw that is fine other than high revs is likely to suffer from a blockage somewhere - sawdust in air filter, fuel lines, air vent, carb, exhaust. Saws that have an air leak will get to high revs but the tuning will keep going off or you will need very strange H or L settings (far away from standard). To diagnose an air leak use soapy water and a pressure/vac tester. If you are really stuck pump the saw to 7 psi, block of the exhaust and air intakes and dunk the saw in a bucket of water.
Just ignore me if you know all this, just trying to help.