What's this going to be? 
http://s185.photobucket.com/albums/x66/mjt60a/new%20project/?action=view&current=longpaperboat.jpg

 Hi Mick, is it Princess Elizabeth?. I think i recognise those cut-in companion ways. regards, Walter

Yes that's right, I thought I'd see if it'd be possible to make a larger hull out of scrap so this one is 49 inches long, more than double the length of the tug (which is 24'')
I'd seen a couple of completed Princess Elizabeth models and thought they'd have looked better if the hull was about 30% longer so I based it around that model....
....of course, now the superstructure would be too short so that also has to be redesigned (I started building it from styrene sheet in the picture) and one or two other things don't look quite right....
....basically, it's not a just a case of altering the kit, I'll have to scratch build the whole thing (just as well I didn't get the kit, bought sheet styrene instead)