Ok heading to the deepest darkest recesses of my memory here.
We all understand 2.5% is required and in a light twin you aint gonna get it.
Convert 2.5% to the RoC you require
find out what RoC you can make
brush the dust off your whizz wheel
Put what you can do on the outside scale against what you should do on the inside.
Look at the alt you need to climb from MDA to end of missed approach on the inside, it will line up with how many feet you can climb. You should raise your MDA by the shortfall.
Av