$recordattrs Expansion in List grids

I would like to place a standard HTML drop down selection box within the List grid that will control the function of a custom button on the same list line.
If I place an object with an ID=Link_type (say) in the grid this is repeated on every record list line - producing of course non compliant multiple copies of the same ID within the document.
However I note that custom buttons with the additional {$recordattrs} are expanded to ID=Button_Name_xx where xx is not record key but is some sort of page elements number that does not actually match the data ID given to the record/line.
I had hoped that the expansion of {$recordattrs} on page generation would append the same 'key' to any ID it found within the <TD></TD> but it seems not to be the case.
Questions I would value some advice on are 1) How is $recordattrs being expanded in page generation? and/or 2) How might I structure a custom dropdown selection class that with the $recordattrs attached would be properly expanded with keys appended that would match the key (xx) appended to the custom button's ID?
An example of what I'm trying. This is the HTML view on the editor page of list. The custom button is labelled "Setup_Sub"
<TD class="rnr-edge" {$recordattrs}>

&nbsp;

<A class="rnr-button button" id="Setup_Sub" href="#" typeid="ib">

Setup&nbsp;Sub

</A>

<DIV>

<SELECT name="Link_name" id="link_type">

<OPTION value="http://xxx/sub_add.php">;

Subscription

</OPTION>

<OPTION value="http://xxx/detail_add.php">;

Detail

</OPTION>

<OPTION value="http://xxx/DD_add.php">;

Direct Debit

</OPTION>

</SELECT>

</DIV>

</TD>
Note: I know that I could do this very much more easily coding wise on a record edit page..but the extra keystrokes really slow down the operation.