+1 on a bolt-on 2" receiver, but be careful that the bolt-on does not rely on your stock hitch to be intact for mounting.
Take a close look at Grumpy's pic, the stock hitch is used for support.
The Kolpin one linked above doesn't use the stock hitch, but I have had trouble with hitches that wrap a U-bolt around the frame bars. Flattened out the frame bars a little trying to get it tight enough to hold the hitch in place, it kept shifting around.
This hitch works well for me, but it also uses those two bolt holes at the bottom.
https://www.amazon.com/gp/product/B002LGO9I0
If this were my rig, I would get those bolts out.
I'd start by spraying penetrating oil (WD-40, liquid wrench, etc.) on it and leaving it to sit overnight.
Then hit it with a 1/8" drill bit and use a center punch and be very careful to get it dead center. Drill a 1/8" hole straight through each bolt.
Then step up one size drill bit and do it again. And again.
I highly recommend reverse drill bits. Using those, many broken bolts have come loose
while I was drilling, before I even got to the screw extractor part.
Go slow and be careful. If you snap off a drill bit or screw extractor in there, you're SOL.
If the bolts come out, great! If not, and you drill them all the way out and the threads too, you can bolt all the way through.