Way too many unanswered questions here.
Has the mechanic ever pulled and replaced a CUCV engine?
Has he ever replaced the IP or worked on a CUCV engine?
Is he going to pull the engine and transmission in one shot? In my opinion it's easier to do that than try to realign the transmission with the engine hanging on a hoist.
You have to disconnect all linkage and electrics and then unbolt the engine/transmission. The radiator and metal grill will have to be pulled to make it easier to get the engine out without damaging the radiator.
It will depend on the mechanics skill and if he is used to swapping engines.