I believe the 4-speed is a L43 transmission, the W56 is a popular 5-speed and found on many HiLux and 4Runner - so lots os places to source parts from. Are you getting just the transmission and transaxle - or will you have access to the donor vehicle? I know they make a L50 transmission (5-speed) that will be almost a direct swap. G50 and G52 were later 5-speeds that replaced the L-series and then went to the all aluminum W-series transmission. The transfer case - I\'m pretty sure didn;t change that much - but you might need a new plate for the shifters - they moved slightly between the models and probably the shift cables. To be on the safe side - best to have the donor vehicle right next to you - as you can pick and pull parts you need or fabrication a new one by using the original as a template. Otherwise, I would get everything attached to the replacement transmission - cables, axles, etc. On Toyota cars - the different series of transmissions are physically similar and will bolt up to the engine (bolt pattern the same) - but the axles and starter bosses (bumps on the bellhousing) might not match up. Might try 4x4wire.com or yotatech.com - two big resources for older Toyota 4x4s - someone there might have already done a similar swap.