I'm currently trying to implement glute bridges into my leg routine but everytime i try to do them it hurts way too much. I've watched Scott's tutorial on how to position the bar and it still hurts me (even with padding), I've tried shifting the bar a little higher and a little lower but it still ends up being really painful. Any suggestions on how to overcome this or an alternative to this exercise would be great.

It's probably just something you will have to get used to. It's something your body won't be used to, a bit like training or even having the bar on your back for a squat.. it might feel awkward and a little painful at first, but as long as it's not hurting you too much and brusing or anything, just try to push through it and you should get accustomed to it 😊 

I suggest you keep using the pad though and you can always post a video for us to check your placement is correct too!