Couple of questions 

The hospital lets you keep your underwear on when you go into OK.
Is it okay to keep your packer on? The thing makes me feel way more confident.

I have quite a lot of chest hair going on. They told me it´s okay if I trim it.
Do they shave it prior to surgery? Don´t really want that  Would be dysphoria hell.
Can I be sneaky and shave it myself?

Underwear depends somewhat on the surgery. Longer duration surgeries they may want to use a catheter or there may be a risk of getting blood on the underwear. As for the body hair, you need to ask the surgeon. They may not want to risk any razor nicks in the surgical area and would prefer to do it. On the other hand, they might want you to come in clean shaved.

Appreciate the input Dena.

Any input from guys who´ve had surgery?
I´d like to hear what your experiences are so I can perhaps know what I can ask.

I also suggest you to ask. I didn't and I wish I would. Got some cheap crappy razors in the morning of the surgery and it took me a lot of time to get rid of the hairs and after that they've grown in causing a lot of acne.
I think you can ask anything related to the process.

I'm going to shave before surgery just to make sure none of that hair gets stuck in or ends up half healed up in the wounds. Hair can carry bacteria after all... If you're particularly hairy I would expect they'd shave you if you didn't yourself before they swab you down with iodine etc. I think they do it on anyone to make their jobs as surgeons easier and cleaner but there's no reason you shouldn't do it provided you don't create any skin irritation in the process?

I don't know about if they allow packers but someone I know of recently went in for surgery and I heard they only requested they wear some sort of DVT-preventing stocking or something. I think they could wear their underwear under that stuff.

When I asked if I could keep my underwear on they had me put on one of those disposable ones instead. Which ended up as a good thing since someone let blood run all the way down there while I was cut open.