The best way would be to post a new comment on this same thread, with the final description. No need to repeat all your arguments, simply summarize it and add any relevant updates from user comments. (You can see an example of how @Cerba updated his latest proposal here).
You would then create the on-chain proposal in Tribeca, and reference the forum post. You’ll need to create a draft first, and activate it 24 hours later.
My recommendation would be to create the proposal on Sunday so you can activate it on Monday. Engagement seems to drop after Friday, so if you create a proposal mid-way through the week, you may “lose” a few days of engagement as it goes into the weekend, and that may affect its chances of reaching quorum.