svt2000contour

I just pulled the head off my '86 SVO to replace the head gasket and some of the exhaust manifold bolts have pulled threads. Does anyone know what thread is on these bolts? I know they are M10 x 1.5, but the thread is either a square or acme or something I never saw before and I have been a Tool and Die Maker for 30 years. Where can I get new bolts? I tried ARP but they only list standard thread. Please HLP!!!

tangerine

Exhaust manifold Bolts: 10mm x 55mm x 1.5 Socket head HD CS Alloy 12.9.
Stock bolts were 55mm & 60mm long, if you put the long bolts in the short holes they would hit the head bolts. put sealant on the threads as they might leak oil/water.