Ok, Here is the formulas I am using.
=QUERY({IMPORTRANGE(X2,AA2);IMPORTRANGE(X3,AA3);IMPORTRANGE(X4,AA4)},"Where Col1 is not null ORDER BY Col2")
It works fine. Everything thing is displayed correctly, It just one column only will display number (####) when I need to to display a combo of number and letter (AB###)
I've a screen shot showing the Red Arrow:
This is the master sheet missing the data in the column
This is the working sheet with the data in the column