you still need a lot of other parts, remapped ecu (vx220 software works best/easier with corsa c) astra g f23 or rebuild the Vectra's box with astra/corsa gear case. no top mount on Vectra box. n/s drive shaft from corsa b 2.0 16v, astra engine mount corsa f23 gear box mounts. custom rad mounts or 1.4/1.8 corsa rad from belt engine not chain, gear shifter from corsa c f23. astra g air inlet pipe, meriva front brake upgrade, suspension.
mine came to around £3.5k to get on the road all in. then another £1.5k to supercharge it and another £1k to add blower cams and forge it and another £3k for the sound system. still need to do more/spend more. be over £10k time ive got it where I want it.
my corsa cost me £450, engine was free. so over £3k in parts, wheels, tyres, exhaust, suspension, brakes, mounts, soon adds up if you do it right and don't get cheap parts that will fail after a year or less.