Your personal loan has fixed payments and you should keep these up. If you don't like the hassle of sending a cheque each month, you should set up an automatic payment for the last few installments.
Both your credit card and your overdraft will allow you to pay any amount (above the minimum for the credit card) off the debt each month. This is what your post is asking for but this is what you've already got, except that you are making two or three payments each month instead of one but, with automated payments, this really shouldn't be an issue.
I would guess that the interest on the credit card is higher than on the overdraft. If so, you should aim to pay off the credit card first.