GM Part # 3730266 Clutch Fork Boot
Applications per the 1938-1965 Chevrolet parts catalog effective date October 1, 1964
0.797 BOOT, Clutch Fork
55-56 PASS (8 cyl.)................(4 11/16 O.L. at clutch hsg. face)
Factory correct applications are your responsibility. GM made part and part # changes with no rhyme but a reason (no production interruptions at any cost).
Application charts and part numbers are for replacement parts that were available at the time of parts book printing.
My observations come from the parts I have in my collection or other reliable sources your parts may differ.
If Factory correctness is your goal, do more research, join car clubs,
forums and buy an assembly manual if one is available for your Project Car (you won’t be sorry).
This is a fun and interesting part of the hobby!