[deadbug]

So, I thought we were ready to take the 9 mile cruise to get ice cream and find out what belt, hose, or other was gonna blow....

Sadly, on a much more local test drive, I found out why the brakes are so jerky. Left rear brake cylinder drained the contents of the MC leaving all the evidence in a trail down the drive.

Recommended by a coworker was Kanter auto parts. But what I found was:

description

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Item # 02014C

Wheel Cylinder 1961 - 1966 Pontiac Full Size Each
1965-66, need front wheel cylinder inner bore diameter 1 1/8" or 1 3/16".

$39.00


$39.00




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Item # 02014D

Wheel Cylinder 1961 - 1966 Pontiac Full Size Set of 4
1965-66, need front wheel cylinder inner bore diameter 1 1/8" or 1 3/16".

$135.00


$135.00




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Item # 02015E

Wheel Cylinder 1964 - 1977 Pontiac Tempest, LeMans, GTO Each
Only rear cylinders available for disc brake cars; $34 each.

$34.00


$34.00




description

price per

quantity

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Item # 02015F

Wheel Cylinder 1964 - 1977 Pontiac Tempest, LeMans, GTO Set of 4
Only rear cylinders available for disc brake cars; $34 each.

So I am left with the following question.....

How do I know if my inner bore diameter is 1 1/8" or 1 3/16" ? or does it matter?

Are they interchangeable?

Really wanna get this old girl on the road to take her to get a finish detail, so I can prioritize what is next. But the brake leakage kinda caused a lot of delay.

She still starts after 3 pumps on the pedal. But she don't move anymore cause I'm afraid we're gonna pop out the other side of the garage.

thanks,
deadbug