I'm about to replace my hood pad as well in my 300TE. After some research, here's my Plan:
1.) Remove old pad, and remove old adhesive on underside of hood (I'm using 3M "General Purpose Adhesive Cleaner", P/N 051135-08984-available at ACME Auto if there's one near you)
2.) Spray underside of hood with 3M "Super Trim Adhesive", P/N 051135-08090. It's made specifically to withstand heat, and is perfect for this application
3.) Apply new hood pad

That's it! Good luck

Michael
'92 500E
'88 300TE

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