67-72 brake pedal arm on a 66???

[66C06]

Ok guys I have a couple of questions...I am looking to use a lokar brake pedal arm assembly and it says it's direct fit for 67-72 C10's. What do I need to do to make this work in my truck? Right now I have a 66 3 on the tree and I was thinking that I could remove the brake and clutch assembly and replace it with an auto assembly from a 67 and use the lokar arm. Does anyone know if this is a direct bolt in or will some modification be needed??? Also, they have direct fit pedal arms that say they will fit a C10 but don't specify year models. I'm going to call for clarification on that but does anyone know the difference between a 90 degree pedal and a 180 degree pedal??? Thanks in advance for the responses!

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