I am looking at doing an engine swap have done a ton of reading on here.

I am going to be over landing with my m725. I know i am never going to get great gas mileage but looking for decent mileage. Also looking to get rid of transfer case while doing the swap.

Engines I've been looking at
4.0 Jeep motor of another inline 6 motor
Stock 350

I do not want to go diesel would love too but unless someone sponsors me it's not in the budget.
Open to other engine options and opinions