To winch or not to winch:
UM,
Not a good idea neighbor as the cylinders will bypass to the packing glands and you wil be putting more stress on the cylinders.
The issues are stability and balance and a winch will ruin that quickly with a light vehicle, bouyancy or not.
What I would do is mount it to the under frame of the the front end loader with a quick attach hitch kit for a 2 inch reciever.
Why do it this way?
The mounting of the winch to the under frame of the loader or the cross frame of the engine mount ensures the proper low point for winching anything and avoids the possiblity of a tip over using the three point hitch or possibly the loader if it is left in the raised position(the loader boom will be too high and increases the possibility of the tractor nose diving even with the boom lowered as the booms hoist cylinders will bypass and lift in the direction of the load being winched.
You may have to have a good welding shop make the adapter plate but it will be much safer.
The other option is whether the cross frame which supports the motor and radiator is thick enough to support a "winch" quick attach tray kit and reciever for the winch tray.
The use of a loader bucket would damage the bucket and eventually stress the boom arms and damage the welds at the upper and lower boom arm weldments.