Ive got to change the two pins at the bottom of the backplate as theyve been mangled and snapped off by the linings when they came adrift. I'm at home and the cars at work so I can't nip out and look at it right now but has anybody removed the pins from a backplate before? Is there an way way of doing this as they appear to be welded into a recessed part of the backplate so I can't grind them off easily from the back. I'm hoping this is going to be a ten minute job solved with a sparkle of mig weld once the old pins are out, but any recommendations on the easiest way or removing them?

New one on me ive welded backplates that were rust holed but never ever had a look at replacing the pins.

I have only once replaced one by drilling and taping, no worries

As Viking sez,
best approach is to drill through and tap to 7mm, then run the bolt in from the back.
Don't forget that you will need to cut the old pins level with the top of the bush on which the eccentric is carried.

ken