“Private Parking. Unauthorized vehicles will be worked over with a sledgehammer…”

A jocular sign about parking has been cited in print since at least 2004 and printed on several images:
   
“PRIVATE PARKING
UNAUTHORIZED VEHICLES WILL BE WORKED OVER WITH A SLEDGEHAMMER, FLIPPED OVER BY AN ANGRY MOB, SET ON FIRE. AND SPRAY PAINTED WITH RUDE SLOGANS IMMEDIATELY AFTER BEING USED AS A GETAWAY CAR IN AN INCREDIBLY DARING DAYLIGHT ROBBERY.”
       
 
Google Books
When Pancakes Go Bad:
Optical Delusions with Adobe Photoshop
By Avi Muchnick
Boston, MA: Thomson Course Technology
2004
Pg. 54:
Figure 2.5
PRIVATE PARKING
UNAUTHORIZED VEHICLES WILL BE WORKED OVER WITH A SLEDGEHAMMER. FLIPPED OVER BY AN ANGRY MOB. SET ON FIRE, AND SPRAY PAINTED WITH RUDE SLOGANS IMMEDIATELY AFTER BEING USED AS A GETAWAY CAR IN AN INCREDIBLY DARING DAYLIGHT ROBBERY.
   
Super Punch
WEDNESDAY, AUGUST 29, 2007
Sign: “Unauthorized vehicles will be worked over with a sledgehammer…”
Photo found here.
POSTED BY JSTRUAN AT 5:46 AM
     
The Tech Game
Rainbow_Dash
(TTG Fanatic)
Posted: Wed. Oct 13, 2010
Unauthorized vehicles will be worked over with a sledgehammer, flipped over by an angry mob, set on fire, and spray painted with rude slogans immediately after being used as a getaway car in an incredibly daring daylight robbery.
 
Twitter
🌸 Ellie ❄️‏
@EllieM72
Unauthorized vehicles will be worked over with a sledgehammer, flipped over by an angry mob, set on fire, and (cont) http://tl.gd/baco6k
6:50 PM - 23 Jun 2011
 
Twitter
NFLNews By Cellounge‏
@cellounge
Photo: Private Parking: Unauthorized vehicles will be worked over with a sledgehammer, flipped over by an… http://tmblr.co/Zpu1qwD_cZnI
10:37 PM - 29 Dec 2011
 
Twitter
Discordian Quotes‏
@discordianquote
Unauthorized vehicles will be worked over with a sledgehammer, flipped over by an angry mob, set on fire, and spray… http://j.mp/A18xLz
5:37 AM - 29 Feb 2012
 
Twitter
Jonathan young‏
@jonathanyoung68
Private parking unauthorized vehicles will be worked over with a sledgehammer flipped over by an angry mob set on fire and spray painted
9:01 PM - 4 Mar 2013 from West Virginia, USA
 
Twitter
herringfingers1‏
@herringfingers2
PRIVATE PARKING:
unauthorized vehicles will be worked over with a sledghammer, flipped over by an angry mob set on fire and spray painted
12:08 PM - 23 Jun 2017