The theme is prepared to allow that. I might be missing something but it should work like this: Cut the following from header.php
<?php if ( $left_col == "on" ) { ?>
<!-- Left Sidebar -->
<td id="left">
<?php // Widgetize the Left Sidebar
if ( !function_exists('dynamic_sidebar') || !dynamic_sidebar(1) ) :
endif; ?>
</td>
<!-- / Left Sidebar -->
<?php } ?>
and paste it into footer.php, right before this:
<?php if ( $right_col == "on" ) { ?>
<!-- Right Sidebar -->
<td id="right">
<?php // Widgetize the Right Sidebar
if ( !function_exists('dynamic_sidebar') || !dynamic_sidebar(2) ) :
endif; ?>
</td>
<!-- / Right Sidebar -->
<?php } ?>
and in header.php change this:
<colgroup>
<?php if ( $left_col == "on" ) { ?>
<col class="colone" />
<?php } ?>
<col class="coltwo" />
<?php if ( $right_col == "on" ) { ?>
<col class="colthree" />
<?php } ?>
</colgroup>
to this:
<colgroup>
<col class="coltwo" />
<?php if ( $left_col == "on" ) { ?>
<col class="colone" />
<?php } ?>
<?php if ( $right_col == "on" ) { ?>
<col class="colthree" />
<?php } ?>
</colgroup>