What dc screw on plugs do you use?

[destro23]

E-outstanding 5-Pack DC-099 5.5 mm x 2.1mm 30V 10A DC Power Jack Socket,Threaded Female Panel Mount Connector Adapter https://www.amazon.com/dp/B07C46XMPT/ref=cm_sw_r_cp_api_i_1-1dDb3ZCF4H0

Something like this?

And which is positive or negative? How do I wire it? Positive in the center? Do I get 10a rating female? Do you guys use shrink wrap?

Also which 5.5x2.1 plug and 5.5x2.5? Is one better then the other because pin is thicker?

Thanks for dealing all the questions

 

[dustNbone]

Generally they're wired center positive. Match them by pin diameter to ensure a solid connection, so 2.1mm with 2.1mm.