if you where going to swap and stay N/A the 5efe is the easiest. basically plug and play. the 4efte is pretty simple to though will involve some wirings modifications. the 5efhe is the same as the 5efe but uses a different ignition and timing system (i hope im right here correct me if im wrong please) and can be complicated to wire up and get running as a member found out much to his dismay. the 4age and 4agze wil need new engine mountings, shafts and probably wired up aswell but it is possible to do!! . the 3gste will definately need new engine mounts shafts and rewired, i also remember that the N/S inner guard needed to be modified aswell to get it all to fit in. anything is possible if you have the right money and the right person for the job! any comments or corrections welcome gerard