PART NUMBER LOOK UP INSTRUCTIONS 
If you know the carburetor you need, just follow the below steps:
1- In the below box, where it says "Search By Part Number", type the part number or model you are looking for. For example HE-19 and click on "Search".

2- You will then see that part number and its price. Click on the Tillotson Part Number.
3- You will now see the "generic" exploded view and the specific parts list of that part.