Is there one available that is bolt on? I want to avoid drilling in the frame.

Also the receiver tube right under the bumper?

 

I have had good luck with Curt hitches from Etrailer. They have one listed for a 1973 F350. I would suggest measure the width of your frame rails and call and double check when you order.

The hitch will probably use holes already in the frame - Etrailer will probably know. If not drilling is not too bad if you have or can borrow a 1/2" drill... mark the hole center with a center punch and start with a nice sharp 1/4" bit for the pilot hole then 3/8" then 1/2".

PS: safety glasses are a really good idea if you drill as the chips will fall down towards you.

https://www.etrailer.com/hitch-1973_...250,+F-350.htm