You'll need the tailshaft and the 4wd rear housing to convert your ax15 to 4wd, and after all that you might be money ahead to just source a 4wd ax15 to begin with.
Driveshafts will be different lengths with the automatic and manual transmissions.
Front axle will be easy enough since the 2wd version is essentially a dummy front axle with the same mounting points. Just make sure it's the same ratio with the rear axle, or just swap both of them
Overall it's possible to do it with what you currently have and affordable if you manage to find some cheap used parts, but your goal with the manual swap is control, then it's entirely possible to convert your AW4 to manual shift. However, if you want the feel of a manual transmission, there's no substitute.