Since they took their time, you can take your time too

You should be straightforward about your work authorization situation as it's a sensitive thing, particuarly for companies that don't have much expertise in immigration laws. Just tell them that you expect to receive the EAD in 30 days and want to make sure that you're in full compliance with the law.

You can negotiate the salary too. As I always say, mentally putting yourself on equal footing as the employer. The two parties are entering into a business deal here. If you feel that finding a job is hard, wait until you are a hiring manager trying to find a good candidate.