Thanks Towager, I've worked out it's 30K - 11500 threshold = 18551 liable to tax. First 10K @ 20 % = 2K. Next 8551 @ 30 % = 2565. About 4565 tax in pounds. (I used .787564 to get the threashold of 14538 Euro to 11449 IEP rounded to 11500 for simplicity - hope this is correct but haven't been doing tax calculations regularly).
I know you've written the interest and penalty but how would that sum go please. Ball park figure please. There must be a formula, easy way to do this. If it's the base rate that would have been quite high in 1993 when some mortgages were circa 15%?