Proper parts should be job 1…. My opinion their shouldn’t be a 727 on track with a stock drum, but you do you . Personally I’d want the blanket properly strapped around the trans. It would take some “robust” tabs around the torsion bars to keep the blanket from deflecting. I’d think the blanket would be better at “absorbing” the energy than the CSR shield. I run the CSR as it covers both the “trans shield” and “flex plate” rules. I still have my old Lofgren blanket for way back that covered the “critical” area of the 727. There used to be a picture floating around from his shop that had a “used” one that had caught the debris hanging on the wall.