Flexplate Bolt Sizes

[cosworth]

I have a 74 Duster with a 318 that was originally a automatic car, that i am putting a 3 speed manual in. I purchased pressure plate bolts that are wayyyy to small, then thinking about it I dug out my old flexplate bolts that are the right size but too short.....

Does anyone know what size this is and where i can find them?

May just need to run down to the hardware store these bolts are only grade 8

 

[cosworth]

I think ive figured it out posting here for somebody to correct me if im wrong.

7/16-20RH with approx .910 Underhead bolt lenght.

Flexplate bolts are 7/16-20 with .50 underhead
Pressureplate are 3/8 with approx .910 underhead

 

[oldkimmer]

..........sounds about right...............kim............

 

[cosworth]

I guess they used different cranks for auto/manual cars?