The replacement connector you are referring to is probably not the solution (though I can not see it because image is blocked) .. You have the Industry standard POL connector (CGA 510) on your regulator now and it is the correct one....Its called the "soft nose" connector for POL... Only other version is a hard nose with out the "O" ring.... They come in two versions, one with with "excess flow" safety device and one with out... All small propane tanks either equipped with OPD valve or not use this connector... Even my 250 Gallon residential tank uses this connector (hard nose)...
About half way down page...
http://www.tejassmokers.com/products/brassfittings.htmHard nose version....

Soft nose version...

The outlet side of connector (male or female thread) is different according to style of device or hose you are connecting to...
IF you have anything other than setup like below, you probably have it wrong (only difference in this pic is regulator is connected to welding hose where you want connection to copper tubing)...


And why is "hex nut" portion of your connect so chewed on looking... You should use either open end wrench or adjustable (Cresent) end wrench... Yours looks like you used channel locks on it...
Dale
Lives his life vicariously through his own self.
Any statement made by me are strictly my own opinion.
You are free to ignore anything I say if you do not agree.
