Does one clean: original heat shields----Never!!!!!
Replace the original heat shielding:----Highly recommended. However,, be very careful when removing it.
Re-manufacture it from non asbestos:---- Good solution
cement it continuous:---No this defeats its purpose.
Is there any benefit in keeping the old, insulation wise,:--NO!!!
Renewing it with the hardboard? :---- Excellent alternative ,is also economical and readily available at hardware stores.
Should I be concerned at all?:--
---OH!!! my goodness yes it is a potential caner generator.
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