904 vs 727

Couldn't find any threads on this.

I visited a wreck yard today and a topic that came up was this one. A man suggested me to keep the 904 in my car since it'll save a lot of work (not sure what work but Im guessing with linkages and length) its ligter and can handle a nice SB if rebuilt properly.

Here is a reply to a question some guy made about the same thing.

"Yes, your stock shifter, linkage, and cross member will work.

But I would question why you're replacing the 904? The 904 can actually be built to handle very high horsepower and has less internal friction than a 727, so more power goes to the rear wheels. It's also somewhat lighter than a 727.

I'd recommend building the 904 with a shift kit and bolt in sprag, add an aluminum front drum if you're making more than 500 horsepower, and it will outperform a 727 in your application."

Now if a 904 is a good option, can I use my 904 on my 67 valiant? or are the later years better? Where can I buy the stuff needed to rebuild and make it handle a small block? Money wise is it better to go with a 727?