A modular engine will NOT fit in an older van, they are much too wide, the newer vans went through serious tooling to fit them, they are set forward to allow room in the passenger compartment. Yes they have a lot of wiring and electronics, but are far more efficient than the older engines, but I'd go diesel if I was serious about efficiency and power. Dad's neighbors son graduated a tech college, they had to build a diesel before graduation, I'm talking design one, he worked with Ford on fixing the 6.0 and 6.4 that replaced it, got me wanting a smoker.