I've wondered how far up the driveway these prints appeared, and where they actually ended. It looks like in this photo there is a police marking tape behind this man at the end of the driveway. (both photos credit to Joy's blog!)
The aerial photo shows where on the driveway the tape was (assuming that is the tape and not a shadow??)
IIRC, the footprints went all the way up to the second light pole? That is quite a ways. I would think they could have gotten some excellent castings of the perps prints as well as the tire casts. I can't believe they weren't able to identify the exact make/year of the tires and put out an alert (which in turn would have supposedly lead to Kevin's car....although I still believe there was a perp vehicle as well).
I think the top picture of the detective spraying the footprints is looking east as the fenceline is on the north. So there are 2 tapelines: 1 on the east(which DR said he could not get his car through but had to drive on the grass in the ditch) and the other tapeline on the west side of the pavement. You can also see the first pole at the abduction site. That pole is not there today so the tracks/prints were about 40 yards long. It appears to me in the detective picture there are multiple tire tracks and one of the tracks appears to be curved. I agree, one assumes this whole stretch of road would have been analyzed for tracks/prints but it has always bothered me that the detective is creating another set of prints himself.