Not being to access some gears, while not being able to access others is not a clutch issue.
I would say there is something up with the springs in the side of the shift tower. The springs are what make the shifter "pop" back to the center position, when you let go of the shifter in the neutral position. If one of these springs is bound up or out of place, or the pin that fits in the springs and rides against the side of the shifter is bound up or out of place, then that would make it so you couldn't move the shifter in one direction or the other. I would pull the shifter back out and push against the springs and make sure they are not bound up. They are pretty stiff springs, so it may be hard to push them, just using your fingers.
And just to make sure, you did put the shift sheet on the top side of the shifter ball (you had to remove the shift knob, to install it), right? The order of install on the tranny shifter is...shift sheet, wavy washer, top plate (with 3 bolts). The tcase shifter sheet goes on top of the shifter ball. The tcase shift sheet goes on the bottom of the shifter ball. There is also a notch on the tranny shift sheet that lines up with the shifter bolt in the back of the tower....make sure it is lined up correctly.