If you have the old paddles, easiest way to get "M-type paddles" is to buy lci-paddles (downshift left, upshift right) or you can cut some wiring inside the old paddles. M3-paddles wont work because of different electrical couplings (M3-paddles are basicly just on/off-type microswitch, old paddles have a small circuit board inside and it basis on different resistorvalues). The lci-paddles are made the same way as the old paddles, only they have removed the upshift-circuit on the other side and on the other side vice versa.
As to the steering wheel removal, you definitely must disconnect the battery before taking the airbag off if you don't want it in your face in worst case scenario! After unplugging the battery, wait for 15 minutes before you touch the airbag, then you will be okay.
Just my 2c