The complete drive over deck system that is attached to the tractor will have to be removed. There's a pin in the front hanger that you'll have to pull (it's spring loaded) in order to swing the bracket down and get it to drop. Then you'll have to disconnect the PTO shaft at the tractor, it will have a collar around it that will have to be pulled towards the front of the tractor to remove it. Then there's 2 spring loaded pins, one on each side, that will have to be pulled to remove the drive over deck system. Then you'll install your snowblower subframe after you assembly it, paying attention to the location of where the stub PTO shaft is at (set up book will give you a measurement, once you set it the first time, you won't have to mess with it again. Install the subframe, put the pins in the front, a big and small one, then twist the 2 T bolts in and tighten the wedges against the front frame. Keep in mind, you'll have to remove your grille guard to install the subframe, if you have one. Then, connect your PTO shaft from the subframe to the mid PTO, hook up the snowblower, latch and pin it on the subframe, and then check the oil levels in the gearbox in the front. This should all be covered in your assembly/owners manual