What size is my rear brake drum?

Did some more digging, and found this on allpar.com, in regards to the 76 a body car, police package.

Valiant pursuit cars with V8s used a wide 70 series police radial (with two plies of fabric cord and four full-width textile cord belts under the tread). The calibrated speedometer ran up to 120 mph rather than the usual 100 mph, while the power steering had a (desirable) firm-feel chuck and an oil cooler. The radiator was larger (22" with slant six, 26" with V8); heavy-duty brakes included front power discs with metallic linings and rear 10 x 2.5 inch drums with automatic adjusters. Interior trim was vinyl, in gold, green, or black, with heavy duty front cushion springs and air foam cushioning, and a full foam front seat-back.

Says the rears are 10 x 2 1/2 inch drums.
Then ya, bigger than 10 x 2 inch.
So, not 11 incher's then.
The other members reply is correct, in regards to no 11 inch.
My error.