It's not helped in my case by several sill covers being applied on top of each other - That's just stupid - weld a plate of rust so you can't see it any more - result inner sills were shot to bits as the corrosion just carried on in an alternative dirrection.
I'm a Vauxhall/Opel nut at heart and they can rot for England and win 1st prize everytime but mini's are much much worse - a 40 K mile 1987 mini has had at least 2 sets of skin sills and umpteen zillion patches in it's life - my 1984 Opel Monza has had just 1 repair and 1 short sill section in its 200 K mile life (I'm not including the 8 point roll cage as a repair )
Theres a place in old town Swindon called allen welding supplies, ive just found they rent bottles cheaper than boc and refill cheaper than boc so well worth a look
If you are looking at good mini sites join Turbominis most members are engineers of some description and you wont get the BS from 5year olds like on TMF
Eyup fellow mini wierdo's. Take a look at this pile that I am trying to make road worthy. Believe it or not the previous owner(s) filled all these holes with resin and filler. They made a right good job, Surely it would have been quiker to weld in new!