I have a chance to buy a fj-40 and i have a few engine choices, I need to know the pros and cons of each. This will be a on and off road truck. My choices are a 4.3 v-6,1985 350 carb, vortec 5.7, and a 6.2 diesel. The 4.3 and the 6.2 will need to be built I have the parts and the skill but this...