What is the origin of the phrase screw you strong letter to follow?

It certainly predates email, as this terse phrasing is typical of telegrams where each Word costs you extra, above a minimum of 6 or 10 Words. I have found references as early as 1978 by Googling for "strong letter to follow". The starting phrase varies. It is usually about as "tough" as current mores will allow. Recently it is "F*** You". I am certain that I saw it in a book of OLD jokes (old then) in the 1950s or 1960s, so you can see that it probably dates back to the early days of the telegraph - 1850s or so.

These days it indicates "I want to send you an immediate negative response, and will follow up with a reasoned exposition of my position." It used to mean "Here is my strong negative response (costing several hours pay); I will send you the details in a letter (which I can send for a penny or two)."