Welcome...
Let me start by saying that my truck has the non-turbo engine with a 5 speed etc but I didn't do the conversion. It was already done when I bought it and it had been done to convert the 40 into a winch race truck. You may get some indications from my thread 'Evolution of my 40' but I can tell you a little about it...
The basics: the 6 cylinder fits but you will not have room for the rad cowl (mine still uses the 40 radiator). My batteries are mounted below the bed but that was most probably because my front suspension was modified to coils with radius arms from a P38 which obviously involved modified inner arches and mounts but if the original l/springs are retained then the batteries can probably stay up front. I have 60 series power steering but if you want or have a PTO winch then you can't use that. I also have 60 series axles which 70mm (?) wider but give you discs on the front.
Over the 17 years I've owned the truck we only really had one major problem with the conversion and that was consistent overcharging. The problem was the 60 series alternator and a 40 series voltage regulator (several of them!) - they did not play nicely together! However we recently solved that by installing a 60 series alternator that has an internal VR and re-wiring to suit the alternator including the sensor wire.
The gearbox mount is the original and the engine mounts were modified - position dictated by the g/box mount.
Have a look at the thread and if you have further questions then, hopefully, I can answer them and if you need them - photos.
Regards,
Rodger
