broken shock absorbeer lower mounting nut
 

Hi everybody,
I'm new on the forum and absolutely clumsy with this kind of "material". And not a native speaker...
The problem;
My rear shock absorbers (nivomats) and springs were getting old. The nivomats did'nt pump up themselfs and the springs were broken at the top. So I tried to losen the lower mounting nut of the nivomat but the nut broke off. The bolt is welded on to the suspension arm. What to do?!!!
Drill out the old bolt an use a bolt with the same diameter?!

Hope some of you have a anser ;-)

Kind regards,

Martijn.

P.S. The photo I just uploaded I found on internet but the nut on the bolt on the photo was broken off.