Repairing a Paslode Stapler

I got these two Paslode 3150/38 W16R wide crown staple guns for free because they have broken and missing parts. The good news is, between the two, I think I can make a functioning stapler. Parts and procedure should be the same for the Paslode 3200 staplers. See links below for the parts and tools I used:

O-Ring Kit & Sleeve Seal (402725):
https://amzn.to/3TYY11o (affiliate*)

Bumper (403855):
https://www.ebay.com/itm/165868645235

Sleeve Flange (405243, if you need one):
https://amzn.to/41PwMbA (affiliate*)

Snap Ring Pliers:
https://amzn.to/3eHsQ5l (affiliate*)

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