Any chance of a pre inflation fixed cheap mates rate deal? That would be a two word reply with the the second word ending in double f
And unfortunately so are the panels you have to line it up with. Rear arches are kind of straight then too curly at the bottom. If you ever had a handful of b-post outer skin repairs - all different curves. I regularly had to cut the bottom inch off them - too curly again. Keeping your eye on that lovely parabolic curve makes all the difference and the best success I had matching the curves from door to rear arch was a ton of filler and a number plate spreader across the two - 90% of which ended up on the rear arch.
Generally speaking though, this is why people make a profession out of it. It is a skill to make panels that are the wrong shape fit. It's normal for pattern parts not to fit. Our job is to make them fit in such a way you'd never know. Once round a bus will either teach you if you're in a learning frame of mind or you'll end up with a bad result, cursing panel makers and never do it again. lol. It's a trial to be sure and not something to rush. A mm or two out shows, it really does.