I can't tell from the picture. But could you sew a piece on that covers the whole area and then mark and trim off the rest?

Even then I think my cuts would wobble. I’m using haartz stay fast material and for someone it tends to guide my shears more than I do. I mark it all out and then cut and it’s just garbage. I would thinking about seeing if my buddy can use his CBC wood router and making me a template I could just ride a razor blade against and cut it out that way.

All hoods of this era would have the excess material what i call "paired out" by that i mean you open up the tips of the shears 2-5mm on the end, hold onto the excess material and slide the shears around the seam, with practice your get a perfect 2-3mm cut parallel to the seam....obviously a sensible pair of shears will be required so the hole thing can be done in one motion and your not hacking at it!

did you make a pocket for the window or are you cutting off window and top material?

Do you sew the ring from the inside or the outside? We call the ring " window frame " by the way. Do you have a technical term for it? When I make this kind of top, whether I make the top with the edge folded in or with piping, I don't put a ring under it. I take a complete piece of the desired material, which is ~ 2.5" larger than the window on all sides. Then I sew both seams from the outside. Then I turn the hood over and cut the material with the closed scissors. And you have a perfect ring - when you have sewn perfectly. When cutting out, it is important, as Gereth says, that you don't chop but push.
In most cases I use vinyl for the window frame for price reasons.

I sewed the ring from the inside. I had it cut out already to size. That may be my issue also. I should leave extra and push to cut like you are all mentioning. If I copy the reproduction like I “think” it was created. This window frame stitch is also what holds the window in.

@Gareth Judd can you explain what you mean by pocket?

If you cut the window to the desired size and make the outer seam of the two seams as the first seam, then you have a "pocket" in which you can insert the window. But also here that it is much easier if you cut out the lower material later.

@Jens Jesberg thanks that makes sense now. That’s not how I did it, maybe thats how I should have. I stitched the window to the top material and then came back with the inner frame piece and stitched that on after.

Thanks everyone for the advice on the pocket method and explaining it to me. I redid the top yesterday and today. That made it way easier than what I had done on the first attempt. Definitely something I’ll remember.

Good tips and tricks guys! ... BUT.... I think we need to work on our cross-pond dictionary! You Europeans have strange words!! (kidding of course).

-A hood is an exterior body panel that covers the engine.
- A trunk in an exterior body panel that covers the storage compartment which is not connected to the car's interior! A boot is something you wear on your foot!
-Gas is the fuel that an internal combustion engine burns! Petrol is an abbreviation for petroleum jelly which you put on your lips when they are chapped.
- A Bonnet is the thing that Little Mis Muffet wears on her head.
- In the states we build door panels. Other places build cards. We give cards to friends and family for birthdays!

Of course I'm kidding around, though I do like to poke at "Gareth Judd" every now and then... (It's been a few years) but we should start a dictionary / reference guide for everyone. We talked about it in the forum before the big update but never got around to it.

It would be nice if we could put together a shared doc. That anyone can add to or edit (anyone in the forum anyway) Basically a list of auto & upholstery terms, where anyone can add a definition. Terminology changes from region to region, not to mention country to country. I can understand how confusing it could be for a new comer to our world. Here in the States soda pop has at least 4 different names depending on what part of the country you are from. It's pop by the way! Not coke, or cola, or soda. I can't imagine how many different names there would be internationally.

Ah, but we put our pants on under our trousers.

@Andy Laird even some pictures with the terms would be nice. I’m much more of a visual person than a written word.

And don't even go with Bangers.