Do not try it out,if you dont want to ruin the game for you,since troops problems are very important for the challenge!!!
Just found that out,when wanted to conquer a caste with 2k peasants-lost,but it was funny

1.Get a fief or something where you can put the troops in
2.Open Cheat engine
3.Example 10 Huskarls,first scan 10,put one away,9 next scan & so on until you have two numers,change them to the value you want
4.Do whatever you want to,but consider,if you go too high,game will crash/lag & the moral will drop.

PS:Same technique also works for upgrading troops:
Example you have 10 Norse Spearman ready to upgrade,but you have 200 of them,damn that will take long,wont it?
So Scan first 10,upgrade the one,then it are 9 & so on,until you get only ONE value,change it to the troops number.
You only have to switch to another troops category or upgrade one of them & you can upgrade all of them for once with strg+ click.

You can do it with your reputation,money,Stats-almost with everything.