The OM617 is a great engine. With that being said they are cold blooded. You will need the glow circuit and relay as posted earlier.
Before putting it in the truck I would do a couple things. Check the rear main seal, Check compression should be 350lbs +, Remove glow plugs and ream the bore and put in the best new GP's on the market. Check the turbo oil drain grommet and tube. check the vacuum pump. and the front balancer bolts. If the IP has the screw in type primer You might want to buy the updated one as those old style can leak and get air in the system. And adjust the valves (required every12-15K)
Also, as Strelnick mentioned check out Peachparts.com. there have been some conversions there that have gone well and some not so well. One issue was the peak HP and tourq curve in relation to the drivetrain.
There are also some other small parts you will need for proper operation. The ignition switch has a vacuum switch that kills the engine, You will have to fab something up to kill the engine or pop the hood every time.
I look forward to seeing more on this project !