i just did this not to long ago.take the whole tbi unit off and take it completly apart.buy the gasket kit for it,i think its like 40 bucks.its not hard at all,i did it in like an hour for the whole process.my truck never ran better too,better gas milage and runs much smother.use carb cleaner and a tooth brush to clean the parts.leaving the unit on the truck and just spraying it down is doing a half ass job to me.its just going to make it look better.when you take it apart there's a lot of little holes and passages in there you cant get to unless you take it apart.mine had tons of carbon and stuff,trust me do it right.