Your message is a tad confusing. If you have an 8n with a swinging drawbar mounted under the diffy.. .. well. .then that is a drawbar??? Yes.. you can use a clevis.. or attatch a trailer ball.. etc. Keep in mind about tounge weight.
You can also attatch to a 3pt ( 11 hole cat 1 ) drawbar suspended between the 2 lower lift arms, for pulling small things like pasture drags. For anything other than that, you would need to get a drawbar lock to keep the drawbar from rotating .. these are simple deviced which more or less clamp to the lift arm, and the drawbar.. preventing it from spinning. You would also want a drawbar 'stay' that mounts between the toplink rocker and the drawbar, to keep the 3pt drawbar from being lifted by the trailer tounge when you come to a stop. Keep in mind that with that stay in place, you must not attempt to raise the 3pt lift.. or you will start breaking things.
Many places also sell a pre-assembled 3pt fixed drawbar.. that looks more or less like an upside down "T" the top side conenct to the toplink.. and the bottom connects across the lift arms.. generally these accept a standard 2" reciver hitch.. tounge.. ball.. etc. But are usually 99$ and up. Easy enough to build your own.. etc.
Soundguy