For protein, I take 75% of the protein content and call them "equivalent carbs". I do a 30/70 combo bolus over 3 hours. This is not something you can do on MDI, but you could take the 30 part since it is given all at once and all up front. The other 70 percent part of the combo bolus is the part that is evenly distributed over the 3 hours.
I agree, you need to get MDI nailed down along with all your ratios etc, before considering bolusing for protein. The calculation of "equivalent carbs" and the 30/70 combo bolus may not work for everyone.
Check
this out... Even fat affects your bg.