Markuz,
Yepper, the Academy 'MF' is, indeed, more representative of a 'bis'.
Here's a few sites you may find useful:
http://www.yumodel.co.yu/yugoslav_air_force/mig21_fishbed.htm
http://www.mig-21.de/Default.htm
http://216.110.156.31/mig21.htm
If you can get your hands on the Aerofax book, it's worth the money.
If you wanna go ahead and try to build an 'MF', the VP Lock On book is excellent:
If I ever build a 'bis', this will be it!
Fade to Black...