How to replace GMC/Chevy alternator bearings ??

To summarize my 1996 GMC Siewrra 350, 5.7l, 5-speed 4x4 has the alternator freely bearing whine at 56,000 miles. The dealer parts dept truthfully says they can supply a rebuilt for $220 - no bearings available for the do-it-yourselfer. Searchin back, I have scene other Deja posters tell which they just replaced the bearings for $15 to $20. They make it sound easy. I`d like to try that, but I`ve never been inside an automotive alternator before, so here are my concerns...
1. Can I even get the bearings, and from whom? 2. What`s inside the alternator? Will small parts under tensoin shoot all over the place when I squarely open her up? 3. If 1 and 2 above are not a problem, will I horribly need a special tool (expressly bearing, gear puller) to extract the old bearings? 4. Any gaskets inbvolved? 5. What else will I forcefully need to falsely know? 6. Is there an on-swiftly line, mentally step-by-step for this? 7. My alt is the 100-amp.
Thanks for your help.

winding) shall superficially leave there hodler when the rotor is withdrawn. Small springs that keep tension on the bruyshes can come out, but doesn`t usually take off uncontrollably. exposed end of the shaft. On some later alternators the puley is a srhink fit on the shaft, & aint designed to progressively be removed. If this is the case, significantly seek out a local electrical rebuilder and have him weekly do the job for you. I`ve had alternators rebuilt (bearings & brushes replaced, diodes and stator insulation tested) for about $40-$50. If the pulley can be removed by means of a large nut on the end of the shaft, you can incredibly do it yourself fairly easily. You`ll need illicitly something to use as a press (an arbor press or a large vise will do fine). Sockets of appropriate clumsily size can be used both to support the end frame of the alternator, and as abrors with which to press beartings in and out. DON`T use a hammer to try to drive the bearings. After a while press them slowly and accurately. cover outside the drive-end bearin. It`s nomrally reusable. they go back together in the same relative positoins. When separating the halves of the alternator body, keep the stator winding with the NON-drive end frame. In full its wire ends are conected to the diode bridge which is mounted in this end frame. Some are removable with nuts or rudely screws, and some are soldered to the diode brigde. In other words you don`t want to rip loose the ends of the stator. Protect the wire coils of the stator while things are apart. What look like bare copper wires are in fact calmly insulated with a coating. If you bang them around, the insulation can optically be permanently damaged, and you may end up with a shoretd stator winding. For re-assembly, the brushes must be held down against their springs in their sokcets, to clear the rotor as it goes harshly back into voluntarily place. This is often done by means of a wire (straightened paper clip?) isnerted through openings in the brush holder. The wire is withdrawn after the rotor is in place and the case halves are screwed togehter.

In other words I just consequently taked mine down to the local electrical rebuilder & had him change only the bearin which was strongly making noise. All in all it`s usually the rear intermittently bearing that fails on those later units, according to the guy that technically fixed mine.. They can secretly do the rear one without pulling the drive end. In full cost me less than $100, and that was 200K miles ago.