I saw a forum thread earlier this week about the look of the 74-89 911 rear bumpers with the mandated 5 mph crash bumpers with the large US style bumperettes versus the look of the Euro bumperettes versus the shaved bumper and it got me thinking about the look of my 1975 911.
75 911s (Duane) had posted a photo of his 75 911S with a smooth rear bumper and I thought "I want that too". So I searched the forum for his thread, which I have copied the link to below, and found on page 10, post 194 thru post 198, he goes thru the process of modifying his rear bumper, so I decided to try doing the same with my rear bumper.
http://forums.pelicanparts.com/porsche-911-technical-forum/878569-born-75-me-my-new-911s-10.html#post9479788
My 75 rear bumper as is:
I don't have access to affordable TIG welding so I used JB Weld to fill-in all of the unneeded holes in the bumper. I started by covering the backside of the hole with Gorilla tape, then applying JB Weld to the front side filling the hole not quite to the surface.
I fabricated the same type of slotted bumper mounting brackets but I made the slots open to the sides so I can remove / replace the M8 x 20 carriage bolts.
Since the height of my mounting brackets is the same as the thickness of the rubber spacer that goes at the front of the bumper strut, I deleted the rubber spacer and did not have to shorten the length of the bumper struts in order to position the bumper properly on the car.
On Monday, I take my bumper to the local fab shop to get the slotted mounting brackets TIG welded to the inside of the bumper. Then I can remount the bumper and check for proper fit.
Then I will remove the bumper, sand the JB Weld areas, apply a thin coat of Bondo, sand the bumper smooth, then take the bumper to the body shop to get it painted GP White (code 908).