oh, and just for clarity, Br1ano, in case you're not familiar with oil changing procedures on gas powered (you guys use petrol, don't you?) cars, it's pretty easy.
First: LET THE CAR COOL OFF> HOT OIL HURTS LIKE MO'.
Next, put the car up a bit so you can get under it, and
carefully unscrew the oil pan drain plug. I say careful, cause if you strip that thing.. oh, boy, you're gonna be doing the mad hop in your kilt fer sho'. (floppy, floppy!)
Make sure you've got your catch thingie for all that dirty oil, and let it flow out.. go wash your hands off while it drips, as you'll likely have some that gotcha in the process. While it drips, take the old filter out, and box it up, and throw it out. Dip your finger in the dirty oil (yes, the dirty oil) and rub some around the gasket/threads of the new filter and screw that sucker in place. The dirt and particles from the dirty oil help to create a better seal, in case you were wondering.
Again, being careful, screw the drain plug back in the oil pan --careful--! and go under the bonnet, and begin adding the new oil. (i assume you know where to put it.

)
Our cars take about 5 quarts of oil, which, in your scottish measurements, is.. i dunno. Add the four, and close it all up, and go for a drive. Get it heated back up again, (don't have to go too far, now) and come back, and while its running, add that 5th quart. Let it idle for a bit after you close it all up, and then you're set to go.
I'm not writing all this out cause i think you're stupid, i'm just covering my bases in case you ARE a newb. If not, good for you, lotza folks don't know how to do this, really.
Good luck, and welcome to the club, we're glad you're here! Feel free to come back with any further questions you may have. I myself am on all day long, everyday, so if you've got a question later, you can be sure I'll chime in somewhere to answer it.
Also, check in the members area for the members list, and see who's also in your part of the world... you may be able to have a first Legacycentral Scotland meet! It makes a perfect excuse to get together, talk shop, and have some beers, and of course, oggle each other's cars..
Best,