Problem battery Cevrolet Trailblazer!

Hello everyone and in advance already a relaxed Christmas time and a good one! My problem: I’ve been driving a Cevrolet Trailblazer 4.2 LTZ, year 2005, approx. 190.000 km. I’m super happy with the car, it’s like a tank or a tractor. Nix breaks that! However, I have problems (almost) with this shitty Alco Delco battery every year! Probably the things here in Germany are already 3 or 4 years on hold, so that when selling only 1 or live a maximum of 2 years… Since I don’t want to buy an (overpriced) Ami battery every 2 years I have now bought an Exide battery. I knew that the poles do not fit and I was aware that they are also switched. OK, therefore bought a pole extension 30 cm. Fits from the length. But now the attachment… A simple nut to screw it up on these standing bolts, after having led it through the hole of the extension does not go! D it is neither an M8, nor an M10 screw! After a long research I found out that an M9 mother in Germany is almost impossible to get. A technician said it could also be an inch screw (whatever that means). Did someone have the same problem and can give me advice? I mean, I can’t weld the poles!!!