If you're going to use tape, might as well go all out and grab the proper double sided thermal tape.....
This is the stuff you want if you can find it.....
Sekisui Thermal Tape Sekisui Product Code 5760 25MM: SEKISUI-5760 at BEST PRICE
If you ask nicely enough, there might be somebody in your area who already picked up a roll and would be willing to part with a foot or so for under $5...... ;)
I've got a roll myself, but it'd cost money to ship it.... best if you can find somebody local. (Besides which my son used half of my roll to "seal" his air conditioner when he installed it this year.......... ).
edit: I've also seen it at Princess auto for a really good price, but that's hit and miss for availability.
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