Counted Out

I recently made a thread thinking that my new shifter was causing me to not be able to get into reverse, but now I'm really thinking it's something else but I'm not sure what.

The Problem:
The car will not shift into reverse while the vehicle (93 Z28) is started. Sometimes you can force it into reverse, but it isn't pretty and often makes a grinding sound while trying to force you out of reverse. This all started occurring after installing a new clutch. The other gears seem to be slightly hard to get into but I'm not sure if that is because of the MGW shifter that was installed.

The Symptoms:
- When the vehicle is off, you can shift into every gear (even without pressing the clutch) except reverse, which almost seems to be completely missing. However,
- if you turn on the vehicle, then shift into 5th, then turn off the vehicle, reverse seems to "reappear" and you can shift into reverse as long as the vehicle is off.
- Other gears seem slightly hard to get into, but I'm not sure if that's because of the MGW shifter or not.
- The plastic strap that comes on a new slave cylinder, that holds the plastic cap on the end of the slave rod to help during installation, is still intact. From my understanding, this strap should break when the slave rod fully extends.

What was changed during the clutch swap:
- Pressure Plate (Ram)
- Clutch Disk (Ram)
- Slave Cylinder (Aftermarket)
- Master Cylinder (Aftermarket, the slave and master were purchased and installed separately)
- Shifter (MGW)

Some people were suggesting to bleed the hydraulics, so I did that today and that's when I noticed the slave strap had not broken. It also seemed to take a really, really long time to bleed the clutch. I was probably "pumping the slave rod" for about 10 minutes before all the bubbles seemed to disappear but the problem continued.

So, where do I begin?