I stripped about 3 of threads on one of my Oil Cooler Nipples when I remove the Oil Cooler Line Nuts.
I would read up on some of the ways to decrease the chances if it happening.
If it does happen there is a repair for that in the DIY section.
When I did Mine I had a 1-1/16 Combination Wrench and also a 1-1/16 Crows Foot (this fit better on the bottom one as it allowed mor positions).

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84 300D, 82 Volvo 244Gl Diesel