This mod works with the Farewell to Arms update.

After finishing the beholster shrine for the first time, the guns do not reset. So if you have the luck of finding a beholster shrine again, you get the 6 guns and the synergy for free. I even changed the accept text box text for you and my other mod Shrine Descriptions also changes its text accordingly! Enjoy!

This does not apply retroactively but I added a console command if you want to cheat: 'beholsterShrine cheat' (remember to use Tab for autocomplete).

Quality of life mods I made:

• AutoReload
• AutoConsole
• Skip Intro And Main Menu
• Shrine Descriptions
• Blank And Active Item Reminder
• Mini Boss Health Bars
• Teleporters Everywhere

Installation
Get MTG:

• Download Mod the Gungeon at: http://modthegungeon.eu/#download
  
• Make sure Enter the Gungeon is closed
  
• Open ETGMod.Installer.exe and press "Step 3: Install ETGMod"
  
• Close dat thang
  

Installing mods:

• Go to your Enter the Gungeon Steam directory, usually located at:
  "C:\Program Files (x86)\Steam\steamapps\common\Enter the Gungeon\"
  
• If there is not one already, create a folder called "Mods"
  
• Drag BetterBeholsterShrine.zip into the Mods folder
  
• If there is a "mods.txt" file in the Mods folder, delete it
  
• The directory should look like this: "Enter The Gungeon/Mods/BetterBeholsterShrine.zip"
  

Then launch the game. If Mod the Gungeon installed correctly, you can press F1 to see the list of active mods. 

Open the console with ~ or / or F2 to enter commands.
Type help for a list of commands and remember to use Tab for autocomplete.
Source Code: https://github.com/Goldenrevolver/Enter-The-Gungeon-Mods/ .