well the problem as I understand it is that wagons and sedans shared VIN numbers so you really only can figure out which car you have from a particular year (last 5 digits).
I compiled a table showing wagon production numbers per year. its on here somewhere...
the Olds are nice cause they were the only model and numbers are sequential.
you have an LT1 so they were all built in Arlington so that at least narrows it down (vs earlier years where Willow Run also built cars).