Absolutely true ! The sum of external Force acting on a solid is null if the solid is at rest
However when you say that you hve just pulled 5G it does not mean that you hve pulled 5g +1G of the normal gravity. It's only 5g (otherwise the G that you feel won't be the same if it was an horizontal turn or a vertical pull up). Then at level flight G =1 . Bank at 60 G=2 (see pic bellow)
By the way that where the Il2 spit was eating E
PS: the neg G cut-out is just perfect : Don't make any modification for god Sake !