GM's 64-81 Corvette Clutch Release Fork.

General Motors "177" Clutch Release Fork is a 1964-1981 Corvette lever.

The Part # 3887177 Fork is approximately 10 3/8",
from tip of bearing retainer end to center of push rod pin hole.
And has a wide beam were it passes through the bellhousing.

I am taking measurements from a New old stock
Clutch Release Lever.

The arch is approximately 1 7/8" at it's highest point.

There is a 3/8" x1/8" slot for a return spring,
and a 1" x 1/4" slot for the lower push rod.

The spring is a standard Part # 3849698.

Note: The 1938-1965 Chevrolet Parts Catalog dated October 1, 1964 lists Part # 3843314 for 1964-65 Corvette

Applications per the 1953-1982 Corvette Parts Catolog Effective November,1981

0.795 FORK
64-81 Y

Y= Corvette

Disclaimer:

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 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!