Frame id ?
 

Did a search and found where to look for frame serial #'s. The fame # I found is S 35123. I found it on top of the driver frame rail. By the power steering pump and just ahead of rear cab mount. Had the same # in both spots. It is a 71/72 I believe. It has disk brakes, 1 1/4" rotors on it. 5lug wheels with a 12 bolt. coil spring rear susp.
The reason I ask is Im getting ready to order drop spindles, And the 71/72 spindle have a different part #. Want to get the right ones. Thanks

Re: Frame id ?
 

If it is a 71 you should have a 1 in front of the S which is for St Louis plant and the rest are sequential serial numbers. (1S35123)

Re: Frame id ?
 

I agree, but there is nothing there in either spot. Any other methods of telling, or will it make a differance with the drop spindle since it already has disk and 1 1/4 rotors.