Trak Day Roll Bar

[BigCol]

I've got a used track day/FIA roll bar and the necessary thin-headed bolts from Carerham but one of the female threads won't bite, so I suspect I need to clean it out (and maybe tidy up one of the bolts too), so
a. anyone know the size of the thread?
b. anyone got a tap and die of the above size I could borrow?

[BigCol]

Thanks chaps... 3/8 UNF is what I've heard from elsewhere too (or from the same chaps under alternatively named logins! )

So, has anyone got a 3/8 UNF tap and die (and handles!) I could borrow very briefly please?