Please could someone advise me as to what is the correct foam used to cushion/seal the heater (98 K-Series S3) from/to the bonnet? I have removed the old 10 x 10mm draft excluder type black foam as it was sadly passed it's best. However, the replacement I have obtained (same dimensions) now seems a tad too firm and the bonnet would sit proud and put stress on the toggle catches. I have now been told that the correct foam is self adhesive strip 25 x 6mm but 6mm thick seems a tad to low by my reckoning..... or am I missing something? Any advice gratefully received!