differnce between a 77 motorhome 440?

Good basic info on differences and Myth debunking;
http://www.440source.com/blockinfo.htm

727 tailshaft will most likly be wrong. It'll be a short tail bolt on yoke and you need a long tail slip yoke. I just did this swap in my Duster. Its really not that hard to do, just getting all the right parts upfront to do it in one shot was hard. Just need the parts, diagram and a GOOD pair of snap ring pliers. I suggest WIT Transmission for your parts(https://www.wittrans.com/Schematic.aspx?Transmission=A727&Schematic=3) They are super cheap and VERY helpful. Otherwise they are both just like any other 440/727.

And yes the mounts will work fine though I recommend the ones by Trans-Dapt. Half the price and the same thing.