I'm preparing for my first belt test in a few months, and I feel like I'm struggling a bit on getting my sanchin form right, particularly with the placement of my elbows and my hips. Now, I know part of this is because...well, I'm a newbie and learning. I also know part of this is because I need to keep working on the strengthening of my lats, shoulders, glutes and abs. Part of it, however, is because of...

I've been told and read some posts discussing a fist's width from ribs to elbow. I believe I want my elbows to protect my ribs, my fingertips to be at level with my shoulders, and my arms to be forward (alot to remember when your still trying to figure it out, btw

So here are some questions.
I can have my elbows a fist's width from my ribs, but they are still resting on my breasts. Is this wrong and will this lead to poor form and laziness?
I can continue to work on pulling my elbows inward (toward eachother) to protect my ribs, but again, they are pressing my breasts together and resting against them. Besides the concerns about poor form and laziness, does this also mean I'm not protecting my ribs as well? I should probably mention this is easier to do when I'm wearing a sports bra...all well and good in class, but that's not going to help in real life if this is ever needed.
Last question, is this a silly question that will work itself out as I train more? I don't think I'm making an excuse for poor form, I'm just trying to work this out in my head and in practice.
Suggestions and ideas welcome. Thank you!