many thanks bill
think i will go for the m45 and use artistic licence and stick a dozer blade on the front
i now it's not correct but hey thats the point of having a scale model if you can't do what you want with it
a bit like the hobart funnies
even the m46 conversion doesn't look to daunting apart from the re-location of the sprocket wheel and idler
but if i went that far might as well do an m60