Regarding sealing wires or connectors with RTV.
As "Soundguy" mentioned RTV is handy suff, and some would work fine.
But,
Many sealants are corrosive to wire and connectors. You can be sure the sealant is wire safe if it specifically states electronic grade or something like that. For example stuff found at
MG Chemicals > Cleaners, duster, silicones, prototyping, epoxy, coatings, lubricants, thermal management and others are elec-grade.
Your home shop sealant (e.g. silicon) is almost certainly corrosive if it smells like vinegar.
I've wired a number of cop cars over the years and always soldered/heat shrink where ever I could. Never use crimp connectors (unless crimp/solder). Some push connectors are fine but use something like Permatexｮ Dielectric Grease here. The same stuff you use on your trailer connector, breaker box...
For a perfectly sealed connections something like this 3:1 double wall heat shrink tubing is great.
Adhesive Heat Shrink : BuyHeatShrink.com : Adhesive Polyolefin : Dual Wall heat shrink
The 3/16" diameter stuff would shrink to 1/16" and creates a hot glue seal. No need for further tape or sealants...
It's very reasonably price @ $2.25 for 4 feet, which should be good for about 30 splices.
It's real easy to use just slip about 1" of the tubing over your soldered wire(s) and apply an indirect flame using a butane lighter. The tubing will shrink snug and glue will ooze out the ends in about 10 seconds. It's best to heat from the center out. You can protect nearby wires, paint... from your lighter flame using Renolds Wrapｮ.
*Not all heat shrink tubing is double wall and lined with adhesive. This type can be identified by its shinny interior surface. Also; some tubing shrinks at 2:1 but it's not as handy and the price difference is marginal for home users.
Sorry- probably boring you
