GM-GMC: Truck question, clutch slave cylinder, clutch adjustment

Question
QUESTION: I just replaced a motor in a 1989 chevy s-10. It is a 89 truck but replaced with a 93 motor. It is a 2.8 litre with 4x4 and it is a 4 speed manual trans. I start the engine and it seems to run fine then after about 2 minutes there is a really high pitched squeal noise coming from the trans area. The truck has a hydrolic clutch, it is low on fluid and it is really hard to push down. What is your thoughts on what this noise could be? The truck had a new clutch, slave cylinder put in , so what can this be?

ANSWER: Throw-out bearing !
The adjustemnt is not correct , and also the bearing might be bad as well

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QUESTION: Can you explain a little more about the adjustment you mentioned in the answer you gave me? I thought it might be the bearing, can you explain how I adjust this when I put a new one in?

Answer
No , The adjustment i was speaking about was the clutch . The bearing just goes bad , There is no adjustment . ..If you purchase a self adjusting clutch all you do is lift the clutch a couple of times and it self adjusts . Questionable on a 89 ?

The clutch adjustment made on the threaded rod .