Ok well I can't advise you on what you should do regarding your doses as generally if you decide to do the split you should only do it under your DSN/Consultants guidance.
What I did was wait until the following 24 hours later to start the split, then take each dose 12 hours apart, each of us has different needs so a split of 60/40 would work well for one, whereas someone else would need to do say 50/50, only time will tell what your split requirements are along with basal fasting tests.
Splitting your basal should not affect your bolus ratios, however if you've got your dose wrong then you will of course need to do a bolus correction to manage it if running high. I would be looking at 3-4 days for things to settle in on your levemir adjustment.
Please run through this first with your DSN/Consultant however as this needs someone who know's your current situation to help you as no one on the forum can advise on what your adjustment should look like.
Hi
I can only tell you what I do which may well not suite you.
I take 10 units at 6 am and 14 units at 6pm ( I need more at night time as I'm asleep whereas during the day I'm expending energy)
I went from an old regime of mixing my own insulin in syringes about 12 years ago and it was very much trial and error.
I wish you well