That is the basic method they use to make a tow truck, so I think it should work well.
Make sure you have several braces to box it out well. I would recommend going with 6 inch c channel, basically as strong as the existing frame.
The only thing I might change is to make it bolt on, using the existing bolt holes for your receiver and bumper.
2013 Coachmen Freedom Express 320BHDS pulled by a 2005 F250 King Ranch CC
A rainy day camping is better than a sunny day at work.