Turbo or None Turbo?

 you will need a sprinter sump and oil pump whatever you choose. buy a turbo it is pointless trying to make a nonturbo engine turbo it is built to a different spec ,the n/a is smooth but slow ,but not as slow as the 617 (glacial) the engine is designated 662, i have drilled 2 of these to fit the dipstick and tube from the engine that donates the sump  ,otherwise you have to change the timing case .......
the job is not too bad ,but it is all done on press fit clearance ,so do not $@£$ it up or its an expensive day out at the merc dealers or breakers for a timing case and the angle you drill the hole at is critical so the dipstick does not foul the sump floor (a light tweek solves that) the blank casting on the cover gives you x marks the spot but do be careful study the hole the stick came from in the other donor cover do not just dive in with a drill you could go through an oil way or worse ,finally round file to fit and use lock n'seal type product for final fit it should knock in with a mallet up to the shoulder create clearance to suit for this to happen ,it must not be loose.
get the injector pump away and have it maxxed and modify the inlet manifold a la mr.brueggers 461 along with the iveco intercooler (pictured),and a freeflow stainless exhaust -160 hp is awaiting your pleasure..
the sprinter sump has to be modified to clear the g mount please read my learned friend mr.brueggers threads on the subject !
he has posted pictures of the job in some detail it is a good conversion and makes a g really go! his one lights its tyres up out of a junction as it steps up onto boost (if you like that kind of thing) very torquey and it is good on the old diesel ,come down on the later dates in september (29-30th) and have a look and maybe a drive ???
please pm me for help on sourcing a 662 turbo and all the parts to make it happen, i take it you have a gearbox flywheel /clutch combo sorted out to fit a 60x engine? the 5 speed out of a 190 e 2.6 is ideal and very good value (under £200 usually on e bay etc)

 musso auto box is married to the transfer case you must use a 60x merc box and attach back onto the g transfer box ,unless you want to build some weird hybrid ,the musso box is a bit dodgy with a bad rep so really avoid if you can , the sprinter sump fouls the g sump on the side where the mount goes (inlet side) and you really should think about altering the sump tank floor if you go offroad at angles as the engine sits up at the front quite a bit ,you will also need the mounts for this engine (see tony b's threads for part nrs. etc) he has info on the thermostat housing and hoses you need to use ,find his threads it is all there on gwoa just have a scroll through look for tony bruegger as a lead name on a thread .

 get reading! hope you don't get any shouts, the overdrive ratio is agood idea as the g auto in a 460 only has a 1 to 1 top gear o/d only on 5 speed and that is electronic and you will need a controller from the u.s. and that is 500 bucks a friend is getting one i await to see how it works. happy reading..

 you will need a flywheel for this and also get the output flange converted to g wagen 8 bolt spec,i can get this done as we do this to the six and five speeders i use ,there is a flywheel available atm that would suit your job , you will need the shift lever and the rods to go with the box also,sorry to cook your brain but its all got to be got and fitted ,the rating on the 190e 2.6 petrol box should be fine for torque as they are built to do 100's of thousands of miles without failure.
manual conversion 
1.gearbox 
2.clutch and flywheel
3.output flange to suit g 8 bolt prop maybe have to alter length of short prop??
4 .pedal box incl.clutch pedal and master cylinder and pipe work
5.gear lever and linkage incl reverse switch
6.gear lever with gaiter correct length so you can reach
7. gearbox rear mount modify
8. if going underwater is your bag drilling and tapping breathers on the box and bellhousing /waterproofing of all openings
9. altering stabiliser frame for manual box
10.phew

 very nice ,and left hand drive ,i see you have kept  the over the top type turbo pipe for the inlet it all looks very tidy have you done any tuning with more fuel and boost or kept it standard musso at about 120 ish?