Create a table with the right formatting, and then run an Append query
instead of a make table query.
You'll need to delete the data first, and then append the new data.
That way you know exactly the right structure of the table, and you can
create Keys.
MakeTable queries are in practice very rarely needed; and if you're
using table datasheet view for viewing or printing, bear in mind that
this is NOT what Tables are designed for.
Why do you feel that a MakeTable is needed? Might it not be better to
create a Form (for onscreen viewing) or Report (for printing), with
the formatting you want, and base it on a Select Query returning the
same data that your MakeTable query uses?