any tips for good choices at an indian restaurant please?

The only advice I can give is just limiting portion control. IMO, restaurant Indian food is maybe the most difficult to guess calories for, and I mostly blame the sauces. You just don't know how they're made. They could be loaded with ghee or not. Who knows?

I'd either just not bother with caring about the calories and have whatever I wanted, or I'd be very careful about portion sizes, and not bother trying to guess which dish has lower calories.

I try to order something from the tandoor, like tandoori chicken or fish. It's oven baked and usually doesn't come with a sauce. Delicious, though.

Sometimes dishes like sag aloo (potato & spinach) or potato and cauliflower dishes are not too fatty as well.

Not filling your whole plate with rice and eating the chunks of meat while leaving most of the rich sauce will keep the calories down a little,too.

Good luck!
Maybe have a small healthy snack before you leave the house
It will help with willpower later.

Skip breakfast, have a low calorie lunch, gorge on Indian food, go back to deficit eating the next day.

This plan worked for me the whole time I was losing weight. I lived down the street from a Indian restaurant where I would routinely eat 3 different curries, naan, rice, a lassi, and the little dessert thingie at the end and I managed to keep on plan. You just have to work it into the overall plan.

3000 calories won't have too terrible an impact on your overall weight-loss plan. That's not even a half pound gain once you factor in your TDEE.

I eat Indian food daily, Stick with Roti verses Naan (roti is about 100 cal a peice) and stick with the dals or saabjis (lentils or vegatable dishes), they are not that bad and you really don't eat that much at one time. Stick away from anything that starts with "butter" chicken, lamb, fish. Simple indian food is not that high in calories really. Oh and stay away from any and all indian sweets and we all know they are loaded with sugar! Hope this helps some and enjoy, I know the UK has some of the best indian restaurants. Don't let the base "butter" or "oil being used scare you because it is used for a big amount they make, but you make ask them not to top more butter on your dish when they serve it. Have fun! :-)