Toyota Repair: 4x4 transmission troubles, toyota sr5 pickup, transmission troubles

Question
QUESTION: Over the weekend I had to use the 4 wheel drive on my 1989 Toyota SR5 pickup.  Now I can not get it to shift out of nuetral with the 4x4 shift lever.  When I move the 4x4 shift lever it doesn't feel like it is connected to anything.  Will driving the truck with the 4x4 in nuetral cause damage to the transmission?  Since the truck has over 322000 miles on it I do not want to spend a lot on repairs.

ANSWER: Is it an automatic or manual transmission? Is the 4x4 indicator light on the dash on? If the transfer case is in neutral it shouldn't move at all so I don't think it's really in neutral, check the shifting linkage for the 4x4 shifter underneath.

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QUESTION: This is a manual transmission and the 4x4 indicator light is on.  How do I check the shifting linkage as it is internal to the transmission?

Answer
Yes, that's correct, my mistake, the shifting mechanism is inside the transmission and the transfer case but since the 4x4 light is on the front differential is locked to provide front wheel drive and it's not in neutral, the indicator light switch is connected to the front differential, when 4x4 is selected the vacuum operated actuator on the front engages a splined sleeve inside to lock the front differential. You can remove the shift lever from the top to inspect why it feels like it's not connected, once the shift lever is removed it can be inspected, you can see the shift rods inside, try moving them manually to see if 4x4 can be disengaged, something happened to this transmission and I'm not sure what, either the shifter is broken or possibly one of the shift forks inside the transmission.