The width seems OK, but the length of 122.2 in (with 3pt hitch) is likely too much for your 8x5. Even if you could get it on the trailer, it's likely that the back wheel will be right at the edge. I am OK with implement such as mower sticking out a little, but I never like to see my tractor wheel right at the edge. You also need to check the load rating of your trailer to make sure. Call your dealer, he'd tell you. Mine recommended a 12ft tandem with elec brake for just the tractor. For one with loader and mower, he's recommending a 16ft.
BTW congratulations on your purchase. As always we want pictures as proof of your purchase. /forums/images/graemlins/smile.gif