[V8Vairs] Kelmark/Mid Engineering drive shaft/cryogenic gear treatment

[Thomas, Robert R Civ USAF AFMC 76 PMXG/OBPE]

Was there a reason the KM/ME driveshaft had to be an inch longer than
the stock part? For clarity, I'm talking about the little rod-like shaft
that goes between the clutch disk and the differential. Could the stock
shaft be used if the bell housing was shorter front to back (not
considering possible strength differences)? Could the stock shaft be
heat treated to make it more resistant to shock and less likely to
break?

Would cryogenically treating the differential gears make them stronger
and less susceptible to wear?

Bob Thomas 
68 Monza