A few thoughts: Giddy is good. 46 is young. My concern is that statement about 'lowering' your personal standards. That can mean anything from sexual to financial ro hygene to ethical issues. I won't pry and ask, but you do need to think about why you feel that way. Don't give away anything crucial to your core, but without flexibility, none of us would ever end up in relationships. Just keep any changes to those that improve rather than damage you.

Feeling giddy at 51, so you've plenty of headroom.
We change, it's what we do as people. He'll change too, if he's worth having.
Define the lines you won't cross and see if he'll meet you there.

Love yourself.

Just be true to yourself. If you find yourself changing in ways you don't like, take a break and get back to 'you'. No man or giddiness is worth losing yourself.

Enjoy yourself. You deserve it!

Just be genuine and enjoy the feelings and don't try to make it more or less than what it is.

46 !!?? You're just a young punk ! Many years of possible love ahead ...

Sorry, my continual failure means I have no advice to get. But am envious that you have found someone who makes you feel that way.

"I feel though I may inadvertently push him away because I lack confidence on so many levels."

This is a dangerous thing to think and say. You know how they say "You can't love someone if you don't love yourself"? If you lack confidence in who you are, you can't be the person someone else needs.
I think you should give it a go. If they're giving you butterflies, just maybe you're doing the same to them!

Just believe you are still young and vibrant. I had a baby at 42.