77 motorhome 440 vs 71 360-what to use???

The main question is whats your budget? The 360 is a relatively simple project with inexpensive(and easy to find) parts into a platform that was meant to use it. Where as the 440 swap consist of harder to find,more expensive parts which are going into a platform that was a handeling compromise at best. All it takes to make a 71 360 run is a good set of pistons that you can zero deck and a decent cam and a set of larger 2.02 valves for your heads.A decent 4 barrel and some cheap headers and you can keep up with most folks. You can use the appropriate 727 trans with either engine.
The 440 motor home motor in 1977 is more than likely a cast crank and the factory pistons are a mile down in the hole because they didnt have any compression.If you just add aluminum heads to reduce weight even with the closed chambers you will need more compression to make it run well.The cheapest headers for this combo are a couple of hundred used and you have to cut your fenderwells to use them.Chassis headers for this combo are $400+ and usually sell for $350 used. When you consider that most 440 stuff new is generally 15-20% higher than small block stuff and used stuff is more difficult to find. You could build a decent small block that would run well and still get fair milage for a fraction of what a decent big block would cost and get terrible milage not to mention how nose heavy a big block A body is.The 727 out of the MH wont work in a car(although you could rob the heavy duty internals out of it) Just my experience,take it for what its worth.