If you are speaking of the 1985 300TD Wagon. 617.952 after you remove the Hoses and tubes connected to the Fuel Injection Pump and Fuel Supply Pump and pop off the Linkage on the Throttle Arm there is a Bracket in the rear bottom of the Fuel Injection Pump.
The Bracket has 2 Bolts holding it to the Block and a single Bolt and nut at the top of the Bracket which is the Bottom Rear of the Fuel Injection Pump.
I would try removing the 2 Bolts from the Block part first and then go up and remove the 2 Nuts holding the Front of the Fuel Injection Pump.
The Nut between the Engine and the Fuel Injection Pump may need a U or S shaped Wrench to turn. But, I did good with a bunch of 3/8" Extensions with a 1/2" Swivel Socket on it. A U-Joint or an Extension with that is made so the Socket can swivel may also be able to be used.
After that move the pump to the read while at the same time pulling the rear of the Fuel Injction Pump towards your Body/the left Fender.
Getting it back in with the timing marks lined up is not as easy.
If you just feel the need to remove that rear Nut and Bolt at the bottom rear of the Fuel injection Pump remove the Oil Cooler Line at the Oil Filter and do what is needed to move it out of the way.
There is also a Spring going to the IP Throttle Arm and to the Bracket.
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