[1lowdiesel]

the 6bt weighs about 850lbs.

personally i would box the frame from front to back as you are putting a torque monster engine into a 30yr old frame that wasn't designed to take it.

the 4BT can get plenty of power, much more than the 200 you've stated. it just takes alot more money and time.

i would say your coils would be fine but i would upgrade to some stiffer shocks if not coil overs.

also you will want to set the engine back as far as possible to distribute the weight.