Personally I would NOT use the 77 for ANYTHING. Mild heat and it lets go. It's a mess to remove when you realize it won't work for you. If it's only a small spot, use the 90, if it's more than a couple square feet of coverage, you'll come out. 15x better buying a gallon of 3m contact adhesive. You can brush the 3m on or if you have access to a compressor, pick up a bottom feed paint gun and spray it on for best results.
No matter what you use, you'll need to clean and prep the surface. Any dust or grease and you'll lose adhesion. Wash the metal with dish detergent and water until the water no longer beads up, let it dry then wipe the entire surface with alcohol or similar paint prep.
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