Tony , have you been at that bloody puzzle and forgot your pills again ? :ihih: ( No offence meant , of course.)
Farmelectrics , i think Tony means you can always use the swa as a earth so you could in fact install 5 pin on a 4 core .
Edit ; But personally i do prefer to run 5 core , i know there is no real need but i just like the reassurance that a good earth is not only resting on a gland that may not have been made off 100% correctly .
And before it is mentioned that the gland should be correctly made off " End of story" , if i made every one off on our firm then i would except that but i don't !