right quite walkthrough. take the pic of the car, get it straight on as possible or the wheels will be different sizes and might look gash.
all this is on photoshop btw but i guess others would work.
basically roughly go round the front wheel with the lasso tool trying to get in some ground, arch and body work. then layer via copy.
do the same to the back wheel.
(it usually works best if u try and get bigger areas cut in the first place uncluding most of the bumpers.)
then with the original background layer transform and make the width to something about 60 or 70%.
when u place the wheels over the old squashed wheels it usually lines up the centres automatically for u as u place on top.
an important thing to try and do is to try and line up any lines such as the sills and doors etc with lines from the squashed original. just so that it looks proper and not stuck on.
all u have to do now is get the eraser tool and cut away alot of the excess with 100% then go down to something like 25% to start blending the arches into the original bodywork.
hope this helps
