I know there are a few long threads on this but I wanted to share the solution I came up with for my old school Slee bumper and tire carrier.
In the center of the tire carrier there is about an approximately 1 3/8 inch hole that goes through to the square tube area behind the tire. I massaged that hole with a dremel so the 1 1/4” portion of a 1 1/4 to 2 inch receiver adapter would slide through tightly. I then payed out and drilled two holes in the square tubing section I’d the Slee tire carrier so I could through bolt where the hole for the receiver pin would go through. This resulted in a very sturdy 2” receiver sticking out of the center of my spare. I wanted to be able to swing my bikes out and also keep them up high. The 1Up rack then mounted there. This rack is an engineering marvel with no plastic parts. I like the results
In the center of the tire carrier there is about an approximately 1 3/8 inch hole that goes through to the square tube area behind the tire. I massaged that hole with a dremel so the 1 1/4” portion of a 1 1/4 to 2 inch receiver adapter would slide through tightly. I then payed out and drilled two holes in the square tubing section I’d the Slee tire carrier so I could through bolt where the hole for the receiver pin would go through. This resulted in a very sturdy 2” receiver sticking out of the center of my spare. I wanted to be able to swing my bikes out and also keep them up high. The 1Up rack then mounted there. This rack is an engineering marvel with no plastic parts. I like the results