AA H-beam connecting rods - problem with bolts.

[GreenTom]

I got a set of 5,5" H-beams of AA. Looks nice, weight is cool (already were balanced here in workshop). But the quality of bolts (which should be ARP) is so poor I can't unbolt them. I tried: 10mm spline and 10mm 12 corner coskets (which are good for most CB, Scat od Bug Pack rods).
This is something between 9 -10mm spline. Any ideas what size of the socket will work?

would be grateful for help
Cheers
Tom

[Chris bugster]

Try 3/8 inch. Should work. Good luck, Tom.

[GreenTom]

Thax Chris. It is what it should be. I hope it will fit.
 I'll try to get it somehow.
Maybe Jasiek has it.

cheers
Tom

[stealth67vw]

3/8" 12 point.