@alien4u do you know where to change the email template for the body text? i can't seem to find it in suiteanswers

Go into the invoice (edit scope), click the "customize" link in the upper right hand corner and then "customize form" There you will find what email templates the custom invoice form is using.

@Marvin Roman this is correct, but that selected template only changed the template for the attached PDF, where can i edit the email body that is sent with it ?

That text cannot be currently customised. You would need to replace the Email process with a workflow driven one to be able to use custom text.

That is what i suspected, thanks for verifying. I will most likely go with SuiteScript then!