I have a misfire on my 1987 ford bronco 2?

I have an odd problem on my bronco 2 2wd automatic. I have a part throttle misfire/hesitation/bucking that will occur when either cold or warmed up to temperature. It will then flutter on deceleration, then idle rough while smelling like unburned fuel/ rotten eggs. Often it will die at idle, then i fire it back up and run excellent, then go and drive it, and it will go back into this odd mode. At wide open throttle it operates normally. I have blocked off the egr, checked timing, checked fuel pressure in relation to the vacuum, undone the exhaust Y-pipe and cats to rule out a melted cat/ plugged exhaust, replaced the fuel pump, ecm, fuel pressure regulator, checked the fuel lines, flushed the fuel tank, replaced the injectors, distributor, plugs, wires, cap, rotor, map sensor, throttle position sensor, fuel filters, air filter, coolant temp sensor, air temp sensor, idle air control, all vacuum lines, coil, o2 sensor, all ground straps, damper, tfi module, torque converter w/ trans rebuild, replaced engine harness w/ one from a wrecking yard (same year, california emissions, auto trans), engine/ trans mounts, drive shaft, new cam, lifters, heads (world products) radiator, water pump, rings, bearings, new thermostat, new hoses, new power steering pump, steering gear, shocks, a/c pump, r134a conversion w/ new receiver drier, new oil pump, oil pump drive shaft, resurfaced upper and lower intake manifold plenums, resurfaced deck on block, magnafluxed the block, new engine gasket kit...after all this, I then decided to take it to seven trained technicians 4 of them factory trained ford specialists, just for them to charge me about 2 hours a piece diagnostic to tell me that they cannot find what is going on. Now I'm wondering why this is happening, cause at this point, i'm just driven crazy!