Got it! So, we have 800563 and 88434, and we'll subtract the latter from the former.

Step 1: We'll start by subtracting the digit 4 and the borrow 0 from 3 in column 1 and get -1.
We add -1 to 10 and get 9 as the first digit of the result.

Step 2: We'll start by subtracting the digit 3 and the borrow 1 from 6 in column 2 and get 2.
2 is the next digit of our result.

Step 3: We'll start by subtracting the digit 4 and the borrow 0 from 5 in column 3 and get 1.
1 is the next digit of our result.

Step 4: We'll start by subtracting the digit 8 and the borrow 0 from 0 in column 4 and get -8.
We add -8 to 10 and get 2 as the next digit of the result.

Step 5: We'll start by subtracting the digit 8 and the borrow 1 from 0 in column 5 and get -9.
We add -9 to 10 and get 1 as the next digit of the result.

Step 6: We'll start by subtracting the digit 0 and the borrow 1 from 8 in column 6 and get 7.
7 is the next digit of our result.

So, 800563 - 88434 = 712129.