Poor man's way to waterproof connections:
Small tube of 5200 from Walmart
Plastic syringe, 3ml (no needle) from Walmart pharmacy
*Take the plunger out of the syringe
*Squeeze 5200 into the syringe from the back end, leaving 1/2" of 'air' at the tip
*Insert the plunger in the syringe
*Fill the butt connector with 5200 using the syringe - push 5200 into one end and out the other
*Insert wires and crimp
It can get a little messy - I use rubber gloves...
This syringe is also great for applying sealant to fastener holes. I use a horse needle (f/ Tractor Supply) to inject the sealant into the bottom of the hole until it comes out the top, then I'm sure I've got good coverage -- especially in the transom for 'ducer mounting.
The syringe method is also good for applying sealant to small areas anwyhere, like a small bead around the seat bases or hatches.
I have also done wires with wire nuts filled w/ 5200.