Ok thanks for the info, I'll look into doing it the way you said. 
With regard to changing the box, it's all down to cost 
(so I might have to put up with the crunching) 
I can drive it alright with a crunch now and then but if my brother uses it he seems to do a lot more crunching than I do. 
Maybe I should charge him for each crunch, that might stop him. 
hahahahaa 
Thanks again for any advice offered.