Stock Clutch Size

[Tdbuilder]

Hi,

I don't post much but instead read and search post for the most part. I have a 1971 Chevelle SS Convertible with L65 350 2bbl and a Saginaw 4 speed transmission. This car has been in my family since the mid 70s and is all original matching numbers.

This past winter I replaced all the suspension with a complete UMI Stage 2 kit. I am now looking to next winter and starting to order parts. Next winters project is rebuild the engine, transmission, and replace the clutch. I could wait until I pull it apart to determine the clutch size but figured someone here could tell me if the L65/4 speed combo had the 11" or 10.5" clutch from the factory. That is question 1. Question 2 is has anyone had experience with Centerforce Clutches? I am looking to soften the petal feel a little since the old knees are getting bad.