onenerdykidLet's just say that the shell works well for your foot. You will definitely want to get footbeds FIRST and then heat mold the liners. Depending on how many days are on the boots, the liners might not mold all that well to you and you might need to get new liners to really make a difference.
The footbed will be a really crucial part in making the entire system function properly. Make sure you do that.
This! Footbeds really help support the foot and keep everything tight. Without one your foot can/probably will pronate and or supinate(Explains why boots can sometimes feel too short, wide and or ankle issues etc.) Not having one will basically throw your foot out of "alinement".
That being said, your liner!...Well, it can only get bigger, so a new liner may be in order. Liners should feel too small at first because once they pack out it offers a snug BUT comfortable fit. But as always, bring it into a shop and they'll help you out. Best of luck!