I posed the supercap question to Davis and got this informative response. The last paragraph is especially interesting.
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We don't recommend customers install supercaps themselve. We prefer to repair it. In theory it should be OK (but we can not guarantee it). There are considerations.
Special care needs to be taken when working with these parts. Improper handling can lead to capacitor damage. When forming the 90 degree bend in the leads, special care needs to be taken to assure no stress travels through the rubber seal on the bottom of the part into the part, as this can damage the seal. This is typically done by holding the part with narrow-tipped pliers near the rubber seal, and bending the leads against the pliers. When installing, special care needs to be taken to (again) assure no mechanical stress travels into the part. Similarly, solder time needs to be minimized to keep thermal stresses from the part.
The part also needs to be affixed to keep mechanical shock from producing stresses between the part and the leads that are soldered to the board. This can be done with double-sided foam tape, silicone gel, or similar affixing.
Aside from this, one or two super-capacitors can be installed. Also, several values can be installed. The night run-time is proportional to capacitance. The reason for our selection was need/cost. The boards was designed to take 10F, 25F or 50F parts, up to two each. They can be mixed/matched in any combination.
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