3-point conversion help.

[California 72]

No, we're not talking football here. The 3-point convertible conversion seatbelts just arrived for the '72 from Seatbelt Planet. Saw the video out there but was wondering if anyone had year specific advice. We are preparing to put the interior back to the original white so there's room for appearance enhancements if someone has a trick or two to share. Thanks!

 

[California 72]

just getting into things now. Looking at the video's out there, the one thing noticed is they all lead back to a CJ's instruction video. They're using a 64-1/2 to 66 model and the metal lip on the quarter is much thinner by comparison to my '72. Once you add back in the rear quarter trim, it looks like there's no room to install the nut. Anyone experienced this and what did you do. For design/warranty purposes, I'd rather not eliminate or modify the mounting bracket and stud for the top mount. All I need is an additional 1/2" or so. Doohhh!!!!

 

[rcadd1ct]

I drilled and tapped the upper mount point to use the same side bolt as the lap belts. I wanted to make sure the top would not break in a wreck.

 

[mrgmhale]

This is a very timely thread/ We have two 1973 Mustangs, one is a Mach 1, the other is a Convertible. Neither has a shoulder belt, which is how they came to us. In the vert I see nowhere in the convertible framing, or elsewhere, where a should belt would mount. With the kits I see in Seatbelt Planet I see some hop for me to be able to get both Mustangs into a safer condition - with every hope we never need to see the seat belts used for the protection of occupants in an accident - ever.

 

[California 72]

Mounting them was a bit of a challenge. As a temp install, I went through the thinner metal of the inner quarter-window sheetmetal frame. It's sturdy but will bend in a wreck. Then again, the idea is not to have a wreck and while it's not as sturdy as mounting them as in CJ's video, it is better than nothing for the very light cruising we use the car for.

What I'm planning is to get longer bolts and drill through the jamb, starting on the outside (or inner to be more technical) jamb. (As in the video.) It also would be a good idea to add a small, thicker, sheet metal strap. There's clearance for it with the interior quarter panel and would add a bit of a warm-fuzzy knowing it's there. That way I can also use a carriage bolt for a more seamless look.

The next thing is to see about incorporating a Roll-bar similar to those used in the '69-'70 Shelby Convertibles. I understand something will need to be fabricated since the car is what? 6" wider? in '71-'73. Otherwise, I'd use one they sell out there or at least did the last I looked.

 

[carguy47]

How about a rivet nut installed into a thick metal area?
If you can also get behind the panel, install a washer for added support.
FYI... I am also dealing with this issue and since the PO installed a 1-piece aftermarket fiberglass roof insert, finding the exact location has bee a challenge!

 

[Stanglover]

How about a rivet nut installed into a thick metal area?
If you can also get behind the panel, install a washer for added support.
FYI... I am also dealing with this issue and since the PO installed a 1-piece aftermarket fiberglass roof insert, finding the exact location has bee a challenge!

I could try to measure the location on my car and let you know, but as you say, it could be a guess at best.
If you can find the original belt mount point. it should be plenty strong as it had to meet government specs back in the day.( I would think). If you have original shoulder belts with mount bracket and bolt, that bolt will be at least a grade 5 and plenty strong.

 

[aasukisuki]

I would love to get some more details on how you guys solved this issue. I also have a 73 convertible, and like others, the CJ Pony Parts installation video does not apply / will not work for these cars. Even if I were to bend the plate to fit the curve of the door well, the bolt isn't long enough to get through the space behind + the trim. I messaged CJ Pony Parts for advice, but never got a response.

Does anyone have photos of what the original belt mount point looks like, or where it was located? I assume all cars would have this mounting location regardless of whether or not the car came with 3 point seatbelts from the factory? If so, I would love to just leverage that for the shoulder belt mounting point.

I started this project back in the fall and would like to get it wrapped up before the weather is nice again.

 

[Sheriff41]

The next thing is to see about incorporating a Roll-bar similar to those used in the '69-'70 Shelby Convertibles. I understand something will need to be fabricated since the car is what? 6" wider? in '71-'73. Otherwise, I'd use one they sell out there or at least did the last I looked.

How about a vertical post on either side, like a cut off roll bar. It would mount to the floor like a roll bar, then extend upward to just below the height of the top of the door where the shoulder mount would be bolted in place. The seat belt would retain the original floor mount positions. This would provide support for the shoulder belt during fast stops/crashes while still allowing access to the back seat and preserving those valuable convertible rear interior panels.

 

[California 72]

wow, forgot all about this thread. Been otherwise preoccupied with a ton of other mind-numbing things. I was just looking at some of the posts, great suggestions! Really appreciate the effort and time. As far as we know, the "converts" didn't have a shoulder belt or at least I can't find anyone who has one factory style. The other problem we're wrestling with is the retractable bottom mount. It's very obtrusive when it comes to the seat track and the belt hangs up between the two easily. Thinking for us, the longer bolt through the mounting spot in the video will be the fix.