Honda HRC216 Mulch Plug

I recently bought a lightly used Honda HRC2162HXC commercial mower (as shown in my photo album) for $450 which I am really happy with (but wish they still made them with cast aluminum decks instead of stamped steel!) and couldn't buy anything new as good for less than twice the cost. However when I got the mower the seller misplaced the included mulch plug, so I had to mow for two weeks and bag the cuttings until he found and couriered the clip to me which he did. First let me say that although I am sure some folks prefer to catch and bag the cuttings, it really isn't my bag. Pardon the pun.
When cutting the grass with the mulch clip in place I am kind of surprised at how much grass gets by it anyway. And when you take it out to clean the machine off, all this grass ends up on top of your grass not dispersed and gone. So I am going to try what I think may eliminated this problem.
I intend to clean and repaint the under side of the mower, after which I am going to fit the plug in place and caulk around the edges to seal them and hopefully stop grass fromm getting by the plug.
I am not worried about not being able to remove the plug easily because it can stay put until I paint the underside again at which time I will remove the caulking, clean, paint, replace the plug and recaulk around it again.
Anyone else out there have the same problem with this plug? What did you do to remedy It?
Thanks John

I have a Honda H3011H mid engine rider and I see that there was an intricate mulching kit available for it, probably quite expensive. However, I also have a John Deere Model 68 rider that I use alternately in the opposite direction on which I've installed a home made mulch plug. Since the JD doesn't have a deep deck or mulching blades, the results are not impressive, especially if the grass is long or damp, in which case it just leaves a mess. And, yes, the plug doesn't seal perfectly and lets clippings fly out in front and behind, which is no worse than depositing a row of clippings on each side from under the deck. Frankly, I think mulching is a hit or miss proposition. Better to just mow more frequently and get shorter clippings.