NEVER assume it is going to be a simple swap. But since the diesel won't be made until 8 years in the future you have plenty of time to think about it. Seriously though, If someone comes forward that has made that swap you should buy a lottery ticket as it's probably quite rare.
I would print out the tech sheets for each engine that show bolt hole locations and engine dimensions. Start going through it reviewing everything that gets connected to the engine and see if it will fit. You'll certainly need a totally different exhaust system. Pay attention to EVERYTHING. Look at the starter & alternator locations. Will your machines cables reach? How about the control linkages. Where do they run? Check the engine mount locations to see if they coincide with holes already in your machine. Look at the intake. How will your connect your filter and intake plenum to the new engine. There are a lot of details you need to check.
I swapped the engine in my 550. An engine swap is often not as easy as it first might seem. Getting the new engine physically in the machine is only 10% of the job. All the other stuff is where headaches are made.