Ok so now that you have your "Crawl Box" and your Adapter Kit, let's move on to your rear case. Off the bat YOU CANNOT USE A FORWARD SHIFT case in the rear. it MUST BE A TOP SHIFT so if you do not have a top shift case you will have to source one or convert your forward shift to a top shift in order for this to work! So remember front crawl box can be either Forward Shift or Top Shift(depending on transmission), but your rear case must be a Top Shift! No but's, if's, or ands about it! So now that you have your rear top shift case you have to gear it. The cool part of this is you can keep stock gears (2.28) in the rear as well and when placed in double low you are pretty much equivalent to a single 4.7 gear set. But I would highly recommend that you upgrade your gearing at this point with a nice 4.7 low gear for your rear case. Just the single 4.7 makes a world of a difference and your clutch will thank you! It's also at this point that you have to make sure you order the correct spline count (21/23) to match the doubler adapter you ordered. Remember if you want a stronger rear case order it up in a 23 spline flavor!
Marlin Crawler 4.7 Gear Set $445
http://www.marlincrawler.com/transfer-case/line-ups/single/new-4701-xd-gear-kit
Marlin Crawler 4.7 Competition Gear Set $549
http://www.marlincrawler.com/transfer-case/line-ups/single/4701-competition-chromoly-gear-kit
Advance Adapters 4.7 Gear Set $349
http://advanceadapters.com/product/2454/477021.html
Once you have everything together it's just a matter of tearing down and rebuilding your cases! It would also be a good idea that at this point you also order and install "Tripple Drilled Flanges" These range in the $20-$25 range.
Has all the common 1984-1995 patterns in one, universal output flange. Includes 4cyl CV and Non CV patterns as well as V6 CV pattern. Makes sourcing and reversing drive lines much easier. Fits gear driven transfer cases and 8" differentials
Marlin Crawler Flange $30 (on Sale for $10 at the moment
)
http://www.marlincrawler.com/transfer-case/parts-upgrade/triple-drilled-tcase-flange
