OK well the 'iceburg' was a false alarm it looks like it was just a spot must have gone from the outside in, it welded up fine after grinding out the rust. coated it with weld through galv and she'll be fine to sand over before i etch prime the body (during 11 days off).
Meanwhile i've finshed the rear passenger support and treated that and then weld through cold galv'd it aswell. as per the pics
Means hopefully I'll get to finish the front patch tomorow night which would virtually garuntee i finish the rear quarter this week and therefore would be on target to finish rust repairs in the first day or two of the 'holiday'.
Finished welding up and grinding back the support on the passenger side.
pic from the front after treating and galving.
pic from the side after welding / galving.
pic of the 'iceburg' after it was removed.