This mod includes QuickKeyboardInput. You can find a list of hotkeys over there.

Description:

• Lets you mix perk decks by picking perk cards from various perk decks (within the same tier)
• Should work with other custom perk decks but haven't really tested
• Please note that most scaling perks require the level 1 perk deck in order to function

Usage:

• Double click on the selected perk deck "Mixed Perk Deck"
• Enter your customization. Example: 1,2,3,4,5,6,7,8,9 uses 1st perk from crew chief, 2nd perk from muscle, 3rd perk from armorer etc...
• numbers corresponding to names are written in the tab view above.

Protections:

• different matchmaking key
• locked to friends-only
• dlc perks can't be used
• locked perks have no effect

Feel free to post your interesting customizations in the comments.