Minecraft Launcher: (You may experience some bugs in beta using vanilla launcher)
Step 1. Open the launcher, navigate to the "Settings" located at the bottom left of the launcher
Step 2. In the settings enable "Show historical versions"
Step 3. After enabling the historical versions, go back to installations and add "old beta 1.7.3"
Step 4. After creating the beta 1.7.3 version, launch it.
MultiMC/Prism Launcher: (Best for modded instances)
Step 1. Download and install MultiMC/Prism Launcher from the official website.
Step 2. Launch MultiMC/Prism Launcher and create a new instance.
Step 3. Select "Betas" and click on Beta 1.7.3
Step 4. Click "OK" and launch the game.
Step 5: Then simply join alphaanarchy.org, and you're done!
*AlphaAnarchy does not condone or encourage the use of any unofficial clients, utilities or modifications that may be against Mojang's EULA or other policies. Using these modifications is at the risk of the player, and AlphaAnarchy DOES NOT take any responsibility for any damages caused. For any issues please contact @alecsmz on Discord or email me: @alphaanarchysocials@gmail.com