Henri:
Are you looking for 3 view drawings, or are you looking for plans to build from?
I have a few pages from the Aerocommander 680FP (full scale) maintenance manual which includes a spec sheet, 3 view with dimensions, cowling, landing gear, instrument panel, and other details.
I have built a 50" span model from these drawings for a pair of OS15s, the model was a beauty and flew great - and that was over 20 years ago. (Lost the airplane to transmitter battery failure).
I do not have plans for you to build from for your MVVS.21, but if you can design and scratch build, you might like the Aerocommander 680FP.