Prevost engine swap possible?

With a big enough hammer, all things are possible.

I just sold 1972 Prevost with 8V72 and made 400 miles delivery trip with it.
Detroits are consider drippers as lousy mechanics don't pay attention to them.
I made my Detroit dry. All it took was new valve cover gaskets and paying the attention to alignment. Problem was that with 2 center bolts, the covers can play about 1/2" around and if you don't pay attention, miscenter covers will drip.
Bare in mind beside valve covers the 44 years old engine is likely on all original seals.
Fuel economy? I keep the log book and over the time my mpg on 16 tons coach were 5.5-6.2 mpg.
The only complain was HP/lb ratio as with 318 HP that thing was slow on grades, but will cruise 70 mph on flat.
Than why Cummins?
Put Mercedes in it. ;)

Yes, that chassis was built to accommodate several different engines, depending on the specifications of the original purchaser.
But why go for another Detroit Diesel? Why not a Cummins?
All it takes is money and time...

Personally I would contact Prevost directly. I'm sure that they can be of help. Prevost chassis buses are used in fleet applications and they are designed for major repairs and engine swaps with a minimum amount of downtime, if you have the right equipment. You should be able to find a used engine out of a wrecked chassis.