INSTALLING A MARLIN CRAWLER BOX ON A CHAIN DRIVEN TRANSFER CASE.
This installation is on an '02 Tacoma with the 3.4 liter motor and the automatic transmission. However, most of the information will still be the same when installing a crawler onto any chain driven transfer case on the 95 and up auto Tacoma's, 4Runners, Tundra's, FJ Cruisers, and Sequoia's. The Marlin Crawler box to the right is for the 3.4 liter Taco or 4Runner with the automatic transmission.
The side of the cawler box
Front of the crawler box
Rear of the crawler box
For those of you that are not quite sure what a crawler will do for you, this next section is for you.
A crawler box,( in this case a Marlin Crawler Taco box), is the reduction portion from an early model Toyota Hilux 4WD truck.  It is the portion of the transfer case that gives you the reduction in gearing between high and low.  They came with 1:1 and 2.28:1 gearing in stock form.  Marlin Crawler has installed their 4.70:1 gears in this case giving it more control and options for the owner. 
The Crawler box is placed between the transfer case and the transmission.  When installed, it will increase the length your drive train by 8.5 inches.  You will have to shorten your rear drive shaft, and lengthen your front drive shaft to accommodate a crawler box.
You will also have to find a place to put your extra shifter as you will now have two of them    if your dealing with a '95 to 2004 Tacoma.  The newer Tacoma's with the auto transmissions have a switch on the dash that controls your transfer case so you will just have your tansmission lever and your crawler box lever.
Now, onto the install.  First thing to do is to start taking your interior apart.  You will need to get the console apart and pull your stock shifter off.  This is the area that your crawler shifter is going to come up through.  Note in the picture to the right that the stock shifter has a set of wires to the shift knob that will need to be extended, but more on that later.  There are a number of 10mm bolts that will you will remove from the metal trim plate that surrounds the shifters.  Once that is off you will be able to take off the shifter boot and you'll have access to the shifter base plate so that it may be removed.
Interior of a 2002 Tacoma V6 with automatic transmission
Also note, that when you take the stock transfer case shifter off, there is a small screw that holds the shift knob onto the shifter lever.  We put tape around it so we don't loose it. You may want to do the same.  You will also note that there is a set of wires that will need to be lengthened that go to the 4wd engage button on the side of the shift lever.
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These are the wires on your stock shifter that will need to be extended
Secure the small screw that holds the shift knob onto the shifter
Next,