RE: what type of solder to use
I agree with the guys using 60/40 solder. I've used it for some 40+ years on both 2-56 and 4-40 hardware with never a failure and lots of this has been on overpowered 1/4 scale planes. Just make sure you have the joints clean, clean, clean and use flux with adequate heat and you will have no problems or failures. Sure, the Staybrite works fine and if makes you feel better, use it. If you just want adequate strength and less cost, go with the 60/40 for that purpose.