How To: Download and Install iOS 4.2 On Your iPad, iPod Touch or iPhone Pre-Release..

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iOS 4.2 Gold Master was made available to developers yesterday, but the rest of us are waiting for our turn with the new operating system. New iOS 4.2 features include multitasking and AirPlay functionality as well as wireless printing directly from the iPad.
Hey! We have an idea; let's download it now!
First thing's first, and most of you probably know this, but we have to say it anyway: Do NOT do this is you have a jailbroken or unlocked device, unless you want to risk losing the jailbreak. 
Another precaution, please remember to back up your device. If anything should go wrong, you want to have a backup.

1) First, you will need the iTunes 10.1 Beta, because 4.2 won't work with the previous versions.
We found the file at the following locations:
Now install your iTunes Beta:
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2) Now you must download the IPSW files. 
This one worked for us: 
Fair warning, it's a beefy download at just over half a gig and places to download from are in high demand right now, so you will be waiting for a while:
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(a very long while).
For simplicity's sake, move this file to your desktop once it's downloaded. 
Here is the iPhone version (requires iPhone 4): iPhone3,1_4.2_8C134_Restore Firmware Download (Check here too)
You may also want to check here for your other device downloads: iModZone

3) With Your iPad plugged in, click on "Restore" while holding down the option key (OSX) or the Shift key (Windows). 
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4) Choose the IPSW file you just downloaded. Your iPad will restore with iOS4.2
5) Now you must use your backup to restore all your Apps and settings to the iPad.
As a sidenote, the install and restore process takes 15 or 20 minutes, so make sure you have plenty of time to sit around and wait.
You should now have iOS 4.2 running on your iPad. Say hello to iPad multitasking!