I recently began restoration of a1964 TR120.  The heads of the bolts for the name badges and parcel grid on the gas tank were ground off.  I "easyouted" the studs and cleaned up the threads.  However, after purchasing new parts the bolts do not fit.  I reordered the bolts from a different supplier and they do not fit either.  Anybody have this problem?  Did Triumph change threads from year to year?

Rich