I'm planning to get rid of my ext reg Alternator for the internal one. But a friend asked me If i can use his spare off his 99 Chevy truck. Is that possible for me to use the Alternator off the 99+ chevy trucks. Wiring? Amps?

Thanks

No...the clocking on a '99 Chevy Pickup is wrong, if it is a straight clocked alternator (meaning the mounts are separated by 6 hours on a 12-hour clock). Some chevy models went to a 3-point mounting system or to a 3 o'clock, 6 o'clock scheme. I have also found that the CS alternators generally do not have a threaded top mount, but it is sized almost perfectly to accept a 5/16"-18 Heli-coil. Otherwise you can nut-and-bolt that top connection. The simplest form of a conversion has you tying the brown and blue wires together at the external regulator. Then you simply buy the plug such as the Delco Remy PT1742. There is an adapter harness, but it only goes from an SI (internal regulator) to a CS (can't remember the number). It is simple enough to wire-up though. You can get a CS130 that works for your application by going with something like a 89-91 Corvette or Camaro, or even a Pontiac Firebird. One warning...the CS alternators are fairly expensive. Almost any 10SI alternator will work also and get you away from the external regulator.