I think the stage 1/2 upgrades are by Aero Racing not MMC ? So perhaps the above is correct?
I had the pleasure of driving the Krazy Horse stage 4 M3W at MOG 19, what a machine! Something like 140 bhp plus IIRC, awesome!
Their stage 2 conversion looks good value.........

1969 4/4
1995 plus 8
1996 Plus 4 4seater
2002 Aero S1
2013 M3W
2014 Plus 8