Change GV area in Checkout Payment Page

I am wanting to change the layout of how the gift certificate appears on the checkout payment page, I sent out a batch of GC's last night and have been fielding emails all day because customers got confused about redeeming and using them lol

So I would like if I can to change it from how it currently looks in the first SS to how I have re-arranged the graphic in the second SS

The only file I can find that seems to relate to where I need to make the changes is in includes/modules/order_total/ot_gv.php but quite frankly the thought of touching any code there after looking at it terrifies me LOL and as I understand it, the box to apply GC amount only appears if there's a balance to have applied

Can anyone help me here? TIA :)