Would adding the following to each template file cover it?:

open(TEMPLATE FILEHANDLE,$0);
print "# ",$0;
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$0 contains the name of the file being read. I haven't played with TT (or templates) yet so this is just a hopeful guess.
--
@a = ("a".."z"," ","-","\n");
@b = (12,0,17,10,24,12,14,14,13,26,8,18,26,0,26,
22,0,13,13,0,27,1,4,26,15,4,17,11,26,7,0,2,10,4,17,28);
print map {$a$_} @b;