What you're doing there can be a VERY frustrating job. I would love to see a Honda manual that describes the process. I can only give you MY process. Here is the SHORT version...
Find a nail that will go thru the holes in the chrome leg. it needs to be only slightly small er than the hole...not too loose in there. I've been using long roofing nails. A 8 penny nail might be good too.
Put the black slider on the chrome leg...line up the holes by poking the nail ALL the way thru both parts. If it wont go thru...try spinning the black slider 180 degrees...you HAVE to get the nail thru before you put the spring holder in there...once you get those first 2 parts lined up correctly...dont move anything. Put the spring holder in there and try poking the nail thru. If it wont go...try spinning the SPRING HOLDER ONLY 180 degrees, and try poking the nail thru. All 3 parts HAVE to line up before you can even think about driving in the pin. Once everything lines up with the nail...Poke the nail thru and leave it in there. Put the point of the nail INTO the hole in the pin. WHILE holding BOTH the nail and pin tight together with one hand, use the other hand to push and tap in the pin IN with a hammer, or whatever.
The TRICK...or at least the LAST trick...
Drive the pin STRAIGHT toward the nail...in a straight line...straight toward the opposite hole that the nail is exiting thru. You are basically using the point of the nail to guide the pin toward the hole. You can use the nail for a little leverage to guide the pin, WHILE the nail keeps the holes lined up.
lol...the short version. HOPE...it makes sense to you.
Good luck. If you determine that you actually DO need a replacement part, I got em...for ONE MILLION DOLLARS!!!