Ram Diesel question

From : tl

Q: ok fellas need some advice....i have a 2002 ram with the cummins in the engine compartment there is an insulastion/soundproof piece that goes under what ill call the windshield pan...not the firewall but the part of the cab where the wipers and stuff are mounted. this insulation is missing and therefore causing more noise coming into the cab than should be. my question is does anyone know if this piece makes that much difference in quieting down the cab it costs $120 to replace and i dont want to waste my money if it doesnt help much. thx for any info .