[shadys69]

They look to be over an inch deep

[zdld17]

When you figure most multi-leaf sets have at least 4 leaves at about 3/8" each, do the math and you get about maybe 1 ½" depth , maybe a little more as the spring insulators were about 3/8" each and there were two.. unless your leaves are thinner, that changes stuff.

[Vintage 68]

Originally Posted by shadys69

Ok im confused one guy says 273 one say 331 which one is it? Also what is a radius rod bracket? The number for the year where do you find this?I believe it has multi leaf perches on the rear thats what was in the car.

That's why I used the "If"
If it's not a 1969 10-bolt with that code, then it may have been changed ...
I would always defer to Kurt as knowing more than I do about these vehicles

The others are guiding you through getting the casting dates and identifiers to determine what it really would have been when it left the factory.
BUT, since it already looks like it has been exchanged for an original - I would caution you to spend an hour to pull the cover and check the ratio manually, as no telling what else may have been done up to this point. If I were swapping a 12-bolt into a vehicle for performance, I most likely would not leave a non-performance 3.31:1 in it ...

[shadys69]

It has mono leaf perches verrified that today.I tried cleaning up the area to read these numbers and can see them just cant clarify what the hell they say.