To smoke Cheetos you use a cold smoking technique. You do not want high heat. You can get by with temperatures up to 180 F, but I suggest cold smoking, which is generally below 90 F.
Place the 4 lit briquettes in the bottom of your smoker.
Add the wood chunk.
Once the wood is smoking, you can add the Cheetos.
For cold smoking (using a smoke tube)
Fill the tube with the wood pellets. Place into the bottom of your smoker and light one end. Once the pellets produce smoke, you can add the Cheetos.
For the smoked Cheetos
Place the Cheetos in an aluminum pan over your cold smoke setup that is already producing smoke (from above).
Smoke 20-30 minutes, gently tossing once or twice, until the desired smoke taste is achieved.
It's best to let the smoked snacks sit out for a while before serving. The smoke flavor can be a little strong at first. A little rest time will mellow it.