Wether or not you like it, the salvage yard is going to be your best source for parts. The thing is you will need to be diligent in your searching, checking back often. I don't know how many of the 4-door 6-cylinders I have seen in the yards with bad motors and everything else ok. Unless you have some room to buy them when they pop up, you are going to be using the salvage yards a lot.

89 SWB, V-6 5SPD, OME Shocks, 16.5X37's, 2"BL, SR axle, Gen2 brakes, Lincoln w/Superwinch