Both silencers have pin holes along the bottom. If I can get the holes welded over/tacked up, would this be acceptable for MOT test? I expect that the plating will peel off around the weld, but as the holes are on the bottom, I wouldn't be too worried about that. Any guidance greatly appreciated, thanks.

Each silencer has two holes, yes?

If so, leave them. They're supposed to be there!!

They help condensation drain out

If you mean other holes that have rusted through or something, yes, weld 'em up and all will be fine.

Each silencer has two holes, yes?

If so, leave them. They're supposed to be there!!

They help condensation drain out

If you mean other holes that have rusted through or something, yes, weld 'em up and all will be fine.

On closer examination, there are 3 holes in the top one, 2 off which are already welded up (these look like a pair in line. On the bottom, there are 4 holes, 2 are welded up (again these look like a pair). Whoever welded them up made a terrific job as they have been plated. Open holes are clearly manufactured, not rusted through. Many thanks for your help.