Broadcast sheet question

[mbxlesney]

Greg.....On the Fisher broadcast seat sheets in 1969, I have noticed a few of these over the years with the L78 but have never seen one with L34. Did Fisher Body use this as the generic code for the car having a BB like using the M20 for the manual transmission? Also was the L78 listed solely for the purpose of the heater box differences? I owned a 1969 Nova SS that had L48 and N10 on its seat sheet. I also always wondered what become of all the Fisher body records and why they would not be a viable source of info instead of trying to convince Chevrolet to dig up all their records like Jim M. was trying to accomplish.