Got it! So, we have 55104 and 15887, and we'll subtract the latter from the former.

Step 1: We'll start by subtracting the digit 7 and the borrow 0 from 4 in column 1 and get -3.
We add -3 to 10 and get 7 as the first digit of the result.

Step 2: We'll start by subtracting the digit 8 and the borrow 1 from 0 in column 2 and get -9.
We add -9 to 10 and get 1 as the next digit of the result.

Step 3: We'll start by subtracting the digit 8 and the borrow 1 from 1 in column 3 and get -8.
We add -8 to 10 and get 2 as the next digit of the result.

Step 4: We'll start by subtracting the digit 5 and the borrow 1 from 5 in column 4 and get -1.
We add -1 to 10 and get 9 as the next digit of the result.

Step 5: We'll start by subtracting the digit 1 and the borrow 1 from 5 in column 5 and get 3.
3 is the next digit of our result.

So, 55104 - 15887 = 39217.