There are a few welded studs in the MGA. Some are small, like #10-32-UNF to mount the radio speaker grille or blanking plate behind the dash. Some are larger like 3/8-24-UNF for rear ale rebound straps or 1/2-20-UNF for front bumper mounting.

Most of the weld studs in the MGA will NOT have a part number in the Service Parts List, because they were originally welded into another assembly, therefore being non-serviceable. Find a list of captive fasteners for the MGA in tech article CF-160 in the Care And Feeding tech section. Most weld studs in the MGA are fine threaded (UNF), and most will have a shoulder on the shank as a mechanicla stop (like a shoulder bolt).

If you need to replace a damaged shoulder stud you might have to make your own part,and it will require ginding out welds and/or cut and weld for repair. As such, you should pay special attention to trying seriously not to break the welded studs, so maybe you won't need to replace them.