Automatically Fill Up when a Cell is Blank

I do race car lineups on an Excel 2007 spreadsheet. I use a series of cells to enter car numbers for each race, example, series B10;C10 down to B20;C20. I often have to take one car out of the lineup and re-enter all the data from that car down. Is there a way to have it automatically fill up if I remove a number from one of the cells. Example, in the series above, if I took out the number in C12, I would want B13 to cross over and move up to C12, then C13 would move over to B13 and so on. Thank you for your time.

I'm not sure if this answers your question

Do you know how to use the delete function?
Highlight whatever you want to delete
right click on it
click on delete.

an option should come up with teh 4 choices:
shift cells left
shift cells up
entire row
entire column

It won't work with what you are asking for right now unless you change something.

The cells can only shift up or to the left.

I am not too familiar with how to do formulas, but was speculating that if I could come up with a way in the series of cells to move data around. For example, using the same series of B10;C10 down to B20;C20, I would like B10 to have something that says if B10 is blank insert the value in C10 and make C10 blank, the do the same thing in C10, have a formula that says if C10 is blank insert the value in B11 and then copy those down. This could possibly cause any blank sell to automatically copy up and cross them over. Maybe I am asking for something that Excel is not capable of, but do appreciate your reply. thank you very much.

Does anyone have any ideas on a formula to use for my last reply. something like...Formula in B10 would be: IF(B10)=blank, THEN(C10), THEN Blank out C10. Formula in C10 would be: IF(C10)=blank, THEN(B11), THEN blank out B11 and so forth. Refer the original request above to see the logic of what I want to do. Thanks