Red Line and Shift Point question.

I have a stock '89 S-10 Blazer 4X4 4.3 auto. I was wondering if it was posible to overrev the engine with it in Drive. I ask because I just got it a few months ago and still never floored it because it sounded like a jet engine spooling up and about to blow without the pedal quite being to the floor. It's an old truck with lots of miles and I don't want to kill it quite yet. I was also interested in what the red line is and maybe some kind torque/rpm curves if someone could link me up to some. I will be ordering a tach soon so I can watch the rpm's better.

Thanks

[I]I had an 89' S-10 4.3 with a 700r4 tranny,I added an aftermarket tach. My truck shifted out at 4,750rpm.this truck had an ADS superchip,Flowmaster exhaust without a converter.

My current Blazer 95' model shifts out at 5,500rpm.