I like the idea. How are you going to get the intercooler in there as well as the radiator? Steering could be an issue but a scout or FJ 60 box can help with some of the clearance problems. Maybe stretching the frame and tub behind the doors and in front of the rear wheel wells can solve some of the driveline length and angle issues you will run into. There is a guy on the marlin crawler forum that did something similar to a Willis. But he went with a 1KZ. However some of his body ideas could be used to your advantage. The build thread is called willymamouth. Not sure on spelling though.