Absolutely.  Just use the place geometry manager instead of (or in addition to) pack.

For example:

use strict;
use warnings;
use Tk;

my $GUI = new MainWindow;

my $ROW1=$GUI->Frame(-relief=>'flat',
                     -borderwidth=>0,
                     -background=>'#c2d297')
                     ->pack(-side=>'top', -fill=>'x');

    my $photo = $ROW1->Photo(-file=>"numbers/1.bmp");

    my $photo_canvas = $ROW1->Canvas(-width=>29,
                                     -height=>32,  
                                     -background=>'#c2d297', 
                                     -borderwidth=>0)
                                     ->pack(-side=>'left');
            
    my $text = $ROW1->Text()->place(-x => 16, -y => 16);
    $photo_canvas->createImage(16, 18, -image=>$photo);

MainLoop;
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The above example overlays a Text widget on top of the photo, by overlapping it in Frame $ROW1, with (x,y) coordinates of (16, 16).  Please refer to the Perl/Tk documentation, specifically the pages about geometry management (eg. pack, grid and place) for more details.