Thank you for your replies. PurpleHeart, great advice, thank you so much!
I have a severe macaw and a blue/gold macaw. Both very tame and loving. We're very close and I can kiss their tummies and toes. They've been my feathered kids for many years.

My husband and I have been trimming their toes and wings lately, and I do towel them first just to keep it quick and safe. They don't like the toe grooming, which I use a bird toe trimmer to do. Sometimes I also use a nail file to smooth a rough edge. But immediately afterwards they return to being playful and trusting with us. I've never seen any resentment. More like "what the heck was that? Oh, ok. Play with me now." I can't say the same after the vet visits. After a vet grooming they cling to me, all sweaty, and I have to calm them in the examination room for a few minutes before taking them home. Then at home they become very quiet and distant for an hour or so. This is why I am grooming them at home now. It's much easier on them, and I can use that extra cash I saved for toys.
I should also mention that I work from home and these two are out of their cages all day. They're not used to being packed away in a smaller cage and the car rides. I think between that and dealing with a stranger handling them, there is a lot of stress prior to the grooming. Here, I can just towel them quick, lay them on the bed and baby talk them while I clip and it's over much sooner.

Good call, Bluesbird Exotics

My blue/gold does has a crossed over beak. My severe is fine and doesn't really need a beak trimming because he seems to take care of that himself. But my sweet blue/gold needs help. Yes, sad this must be done, but very necessary. She also has scoliosis, and her head is slightly bent to one side. She can't fly, but she can safely flutter to the ground. But omg she is the most adorable bluegold I've ever seen! It was love at first sight.
I was very fortunate to have two great avian vets, one in CA and one here in TX. They encouraged me to ask questions. Both explained to me each time they dremelled my BG's beak what they were doing and why, and how this assists her to chew easier. I'm confident I can do this. Also, I'm very conservative and gentle and will start out slow.
When I tried to use my electric dremel it didn't seem to impact the beak very well. So I will try the bits PurpleHeart suggested. My blue/gold seemed fine after the one attempt. No one is going to appreciate that dentist drill sound, but afterwards she wasn't stressed out. But maybe I will try a battery operated dremel to reduce the sound.
Thanks everyone for your replies.