Hello, can I convert my 3x9 system on my GT Team Marathon to a 2x10? My main question I guess is what determines if a rear wheel / rear frame dropouts can accept the width of a 10x? The rear of my bike is 135mm.....can 10x fit? I currently have Crossmax SLR with a 9x on them....can 10x fit on them? I plan to sell the Crossmax and replace with CrankBrother Cobalts 3's....will a 10x fit on them? Sorry, just not too sure what determines what. Thanks! Blake