It all depends on what wheels and tyres Terry actually has
ET is usually stamped or cast on the wheel
tyre size is usually on the black rubber part
I never thought of loooking for data on the wheels. Cast on the back of the wheels on the spokes I find K835E INTRA 70645 S363E17, and around the wheels bolt holes DB KE TM XP.
I have in the past used old Senator wheels on Omegas without problem, and used the steel spares similarly, though I did find some Carlton wheels too small to fit over the brake calipers. Assuming they are all 5 bolt wheels, my concern was bolt hole location and central hole size. Basically, will they bolt on a Vectra or not?
you're looking for numbers that are more like 6J17 ET34, which is probably marked near the rim. That gives the width, diameter and offset which together define how well the wheel fits. 5 stud Vx wheels will work, and you can measure the centre hole.
Getting the offset wrong will do weird things to the steering geometry, assuming that they clear everything. As this lot is from your stash, I doubt they'll work very well, and would be very suspicious of the tyre condition as well. A trip to the dump is what I would suggest.