Forgot to post up but after I read this back when I went home and tried it and sure enough, CDan as always is right!
I now have the second button on both of my '97 LX450 key fobs programmed to lock/unlock my '97 FZJ80 and vice versa. It has come in handy several times already...
On a side note...regardless of which of the 4 fobs I have that I use the fobs will work at a much further distance on the '97 FZJ80 than they will on the LX450. Not sure why but I know there have been posts before about the measely operating distance of the factory remotes...Well, that distance is even more measely on the LX than the 80 for me