Did you try using a bottom tap? If not give that a try and then as a band-aid maybe you can use a stud on that hole till you get a chance to fix it right on the next rebuild. DON"T use a cheap imported tap or a borrowed one that has been used way to many times.

1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.38@138.67


Livin and lovin life one day at a time