What is the simplest way to deal with an enumeration list in a fixed-length field?

[Roger L Costello]

Hi Folks,

I have a field that is of fixed length (6). There is an existing XSD with an 
enumeration list of values that can go in the field:

<element name="foo">
     <simpleType>
        <restriction base="string">
            <enumeration value="abc">
            <enumeration value="abcdef">
            <enumeration value="abcd">
        </restriction>
    </simpleType>
</element>

Notice that some of the enumeration values are less than the required 6 
characters. 

What is the easiest way to handle that situation? Is it:

(a) Go through each enumeration value and pad the value with spaces if it's not 
of the required length?

(b) Something else (what?)

Note: I plan to use the "-V limited" option to check the field.

/Roger