re: air injection

[James N Ross <jim@crocker.com>]

Have almost completed reassembly of my 1800 rebuilt engine. Have removed air
injection manifold and want to plug ports in the cylinder head. They are
7/16 in fine. Same as fly wheel bolts. The two end ports need a plug due to
clearance problems with the casting. All the plugs I have found are pipe
thread, not fine. Need help.

Thanks
Jim,   1973 mgb  (Dad's Beauty)