Alex,

Yes the grounds should all be linked together. Anything wheres theres more than one wire links to all the others etc.

The TPS has a ground connection (pin 46 on ECU) which we take car of by connecting to the grounds listed before hand.

TPS Signal is pin 47,
TPS Vref is pin 26

You will also need to ground pin 32 which is the starter motor relay (PATS start inhibitor)

Cheers,
mattr

PS, our V4 isnt an MS :P Its an M-Tech