deserttigger

Hi, I am new to this forum. I have owned a K5 blazer for 12 years. 3 years ago the old straight 6 engine was changed for a 350CID 5.7 litre V8 engine and the clutch was changed at the same time. Now this clutch has failed but the mechanic who did all the work is no longer around. I have the old clutch in pieces and need to order a replacement one but really need help identifying which clutch I need as there are so many choices. For example I just don't know which bit to measure (I have been offered 11", 11.85" and 12" replacements) or how I would know by looking at it whether it has 'teeth' or is 'flat' .