I need to know the thread size of the clutch bleeder valve on the slave cylinder. If someone could provide the dimensions of the bleeder vave screw, length and thread size that would be great.

I need to find a bolt size to plug it so that I can fit my new header on.

 

I believe it's 8mm x 1.25

 

How will you bleed it then? Your best bet would be to just shave off the nipple if you can get away with it. Sounds like a poorly designed header if you can't keep a bleeder screw.

 

You can bleed at the line, or even at the bolt. It is kind of a poor header design though.