The right answer for you may not be the right answer for me or someone else.
If you are hiring the work done and ask my opinion, I'm going to tell you it will cost less and likely end up better if you use a Mustang II based kit or a full frame.
But for me working in my home shop I've decided I'd rather not go that way.
If you are paying to have the work done I doubt you can save any money doing it my way. If you go out and buy the tools to do it yourself, and don't enjoy the tools on additional projects you've probably spent more money doing it yourself.
But if you already own the tools and have the skills to do the work yourself, and you shop carefully, I think you can save money doing a clip or frame swap. If money is short and time isn't, then it becomes a good choice. Not the easiest, but with effort a good way to get it done.
I can't claim to know Art Morrison, but I see his stuff at local car shows and I always admire the quality of the work. (I keep wondering if they will ever finish that Cadillac they display.) But his work insprires me to work harder, not to buy his stuff.
I have somewhere past $30,000 of my own money invested in building a shop and buying tools and I'm not done. Sometimes I make choices based on spending the least money. This isn't one of those situations. Doing it myself if the way I want to do it.