Well taking into consideration that it is already 1902 cheating is all what left. Depending if you playing Vicky or Ricky you have 18 or 33 years ahead which isnt exactly a lot.
I play Ricky+VIP so... If you start new game.
First stabilize economy and acquire money ASAP. You will need $$$ later to pay for all units you building till you civilize. Max spending on education, crime and defense. Taxes at 50%. Above that is a bit risky. Korean revolts are nasty.
With Korea there is a problem of military score. You can overcome it in 2 ways:
1. Praying for event to fire which add 1 division to force pool.

Not working every time, need a lot of luck. If event fire 2-3 times you'll need only 30 native INF instead 60.
2. Turning as many POPs as possible into soldiers. Which give a lot of MP.
Because with Korea you have no capability to buy large quantities of artillery and so on, just focus on spamming native INF. With 60-62 you should break past that magical number 6 (if you have VIP installed, with standard Ricky it is very much impossible - you need 25!). At certain point you will sink deeper and deeper into debt. Even native INF cost a lot to sustain. That is why acumulating wealth is very important. And once you get civilized disband all that rubbish. Dont worry you wont return to uncivilized once you Civilize.
*** I hope it make sense I writing this reply for like 90 minutes, did like 20 breaks because of job commitments. Right now Im wasted, just submiting

o ***