@Sunnysky: So, if I understand you correctly, you're saying any clear silicone sealant has a much higher impedance than the yellow/tan glue that began to conduct (and won't break down over time the way the glue does), so it will be safe to use any clear silicone sealant to moisture-seal the grooves I cut into the glue? Also, only "electronics grade" silicone RTV will be safe in places where it would touch multiple exposed conductors (component leads, exposed copper traces, etc.) that aren't already wired together?
Regarding the "long shelf life" of RTV that you mentioned in a previous post, were you referring to the life of unopened tubes of RTV? I was wondering how long the unused portion of the RTV will be useable, after I open the tube to use a little on this project. (In some other contexts, I've seen the phrase "shelf life" used to mean the life of unopened products.)
Is there any reason not to trust the cheapest "electronics" grade RTV advertised at Amazon? The cheapest I've found so far is $10.19 for 3 oz of
GC Electronic Grade Silicone Sealant / Adhesive 19-155:
https://www.amazon.com/GC-Electronic-Silicone-Sealant-Adhesive/dp/B004SPJN6K
One of the reviewers wrote: "The only issue I have is that the cap does not prevent the tube from drying out very quickly and it is best if used within a few days."
Another brand is
MG Chemicals Non Corrosive Translucent 1-Part RTV Silicone Adhesive Sealant, 85 ml Tube for $12.76.
https://www.amazon.com/MG-Chemicals-Corrosive-Translucent-Silicone/dp/B005T8R6LY
The two products are hard to compare pricewise because one lists its volume (85 ml) and the other lists its weight (3 oz). However, the shipping weight of the 85 ml tube is listed as 3.2 oz, placing an upper limit on the weight of the 85 ml of RTV.