The only attachment that are compatibal from the older GT & GX to the X500 series are the 30inch tiller,Manual lift sleeve hitch & the 42inch Hydraulic tiller. The X500 & X300 Dozer blade and snow blower use a diffrent subframe to attach Implement to tractors. With Blade part itself Yes but you would not get the X500 subframe to stick on a GT200 or GX300 series. Hope this clarifies things :thThumbsU