Okay so '3 in 1' really means 3 different cars but one at a time. I'm actually really pleased with this little idea, it could be a pretty neat little set, similair to the big Ferrari F430 set that was 2 in 1.
About this creation
The full 'set'
The Standard Murcielago.
To convert to a convertible, first remove the roof.
Then simply add a 1x2 studless brick on either side.
For conversion to SV, first remove the standard front.
Now replace with SV front.
Now remove the standard Murcielago side intakes.
replace with SV intakes and remove the back wheels and stock Murcielago rear.
Add the SV's rear end, and put the back wheels back on. Voila, a Murcielago SV.