I'm new to the 80s model trucks but ive been with the dentsides for a while lol I have 82 f250 with i6 and 4 speed, I also have a lifted 78 f150 . I need to get a new clutch kit and seal but there is a 10 inch and 11 inch how do i identify without dropping the trans. it is a completely stock truck if somebody already knows...

 

It could be either one. Where are you going to get your clutch kit from? Autozone in my area carries both in stock for $114. Just take it apart, and then run down to the store and buy the right one.