Originally Posted by KevinS
None of the 58 truck frames measured 180.5”.
Are you saying that none of the 58 frames you checked measured 180.5"?

According to the 1958 Chevy Truck Vehicle Information Kit (clip attached) the frame rail length on 3100's was 180.55". Yours seems to match that dimension. Don't know why others would be different.
Attachments
58 3100 frame data.jpg (134.44 KB, 87 downloads)

Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.