What id forgotten is that the welding of bits in, is actually quite easy, but the pattern making and prep work to try and retain the original shape of everything takes a lot a patience, i could have stuck the new sill over the top and just welded it straight to the part that met, but it wouldn't have looked much like the cabrio sill shape at the the rear, so i'm glad i have gone the extra length to retain its shape.
Really starting to get the love back for these old things!