Dometic awning torsion replacement

[rarebear.nm]

Today I was set the replace the right hand torsion assembly in our Dometic awning, got all of the parts on hand. According to the instructions you need to use a 7/64 x 2 3/4 cotter pin to lock the spring shaft to the housing. The left side is built that way as is the replacement torsion unit. However, the right torsion unit does have the two though holes like the others. Three is only a single hole going straight into the tube. How do you safely lock the spring while removing the arm?

Existing unit, single hole



Replacement two hole for a through pin, matches left hand unit