Why are you opposed to having a parking brake? GM backing brackets are cheap and readily available. Easy swap. never mind i actually read your other post. So you have a left and right bracket already?
Tobin does have a bracket for the LS conversion. Give him a call, he has always been helpfull to us in the past. See if you can buy just the brackets.
http://www.kore3.com/proddetail.php?prod=10277-01