Is your 84 motor a true 84? Not an 85 or above? Does it have the pear shaped exhaust ports on the head? or Round?

Reason I ask is that IF the fresher motor is '85 to '95, You can use the intake, with all sensors, and exhaust mainifold and bolt those to the carbed long block. Plug and play really. BUT, if it is indeed a shorter '84 block, then you got me there.

85 4Runner - With NEW Marlin 4.7 Gears!! It's a whole new beast!