Driveshaft length

[herb101]

Anybody know what to expect for the stock dimension of a rear shaft for a 350/TH350/np205 equiped 71 Blazer K5? I'm wanted to compared my shaft dimensions (collapsed and extended) to stock to see if the PO made driveline mods when the lift was installed. I'm tooling up for the 700R4 install and I 'think' I can absorb some added length of the spacer option, due to a too-short shaft now installed. I am under the assumption that the shaft is stock length by the spline length exposed, but I was looking for some tangible numbers to make sure.

Thanks - as always,
Herb