Fukoku Kyōhei II Strategy

I'm trying to build a strat around optimized production, to abuse this policy in modern for absurd science boosts, but am having trouble coming up with the best leader/civ combo to make it really pop.

I had thought to try Alexander due to his 10 then 20% production boost in cities with wonders outside the capital, but keep finding myself with a fairly weak antiquity which is fair, but really idk if this will be worth it or very fun trudging through exploration since I won't really pop at all until modern.

Idk if this is the best choice, and at that, unsure what civs for antiquity and exploration would be best.

In a prior attempt I used Ben Franklin and focused on economy leading up to modern, then spammed naval units, but ended up losing to Pacha culture victory right as I was about to finish rocketry, so it wasn't strong enough that time.

I want to enter modern with essentially all my settlements as cities, then rush the policy card, to spam naval units for the science boost and hopefully, speed through the tech tree for a fast science finish.

TLDR:

In your experience, in order to have the most insanely productive cities entering modern, what leader is best to take, and what civ for antiquity and exploration, knowing I'd be heading into modern with Meiji Japan?