ssnake-oyl does nice work, for sure.
I went through a similar effort when trying to replace shoulder belts in my LeMans. It came with the deluxe belts, and when trying to get the right shoulder belts, I found out just how many differences there were.
So not only are the tongues different on some types, but also the buckle/receiver size, and some even have the loop & knob style retainer.
Then when trying to update the standard belts in the 442, went through it again trying to find the deluxe belts I wanted. I ended up with a bunch of leftovers, ones I still have today.
I finally, after much searching, found a thread here where the differences were outlined, and wish I could find it now, I would give credit to the original poster. I have the original URL, but after swapping maxperformanceinc in place of performanceyears, it doesn't come up:
http://forums.performanceyears.com/f...lt+differences
But luckily, I saved the image that was posted, and attached it.
There's another good reference on a Camaro page, some applied to all GM cars:
http://www.camaros.org/seatbelt.shtml
Now, with that listed, my '71 LeMans Sport, which came with deluxe belts, had the large receiver and buckle for the front shoulder AND lap belts. All the buckles and receivers in mine were the large style, and I'm fairly certain, like 9.999% sure, they had never been replaced, and were installed that way from the factory. When I redid the interior at one point, I had all the belts out, and when I installed the headliner, I left the shoulder belts out, since I never used them anyway.
I was going to go to Summit Point for a track day, road course, and was rejected at tech for no shoulder belts, which is why I went through the effort to replace them. Hence my research, and extras.
A set of restore belts are not cheap, especially if you want particular date codes. As an example, the deluxe set I bought for the 442, which came with standard belts and wanted to upgrade, without date code/tags, was $650, and they were 'seconds'.
If you got the homework done in 4 hours, you did REAL GOOD. My fiasco for the LeMans lasted about 4 months. And on the 442, since I waited for a deal to show on eGay, lasted about 10 months.
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