Yes, it's possible for you to pursue an LLM in Taxation Law at Government Law College, Coimbatore, even if you're currently residing in Chennai.

Here are the general criteria you'll need to fulfill:

1. LLB Degree: You must have completed your LLB degree with a minimum aggregate score (usually 55% or higher). Your 8.7 grade suggests you meet this requirement.
2. Entrance Exam: Government Law College, Coimbatore typically conducts an entrance exam for admission to their LLM programs. Check their official website or contact the admissions office for specific details about the exam and application process.
3. Domicile: While domicile may not be a strict requirement for non-resident Indian students, it could be advantageous. If you have a domicile certificate from Tamil Nadu or Coimbatore, it might enhance your chances of admission.
4. Application and Documentation: You'll need to submit a completed application form, copies of your LLB degree certificate, mark sheets, and other required documents as specified by the college.

It's advisable to visit the official website of Government Law College, Coimbatore, or contact their admissions office directly for the most accurate and up-to-date information regarding the admission process, eligibility criteria, and specific requirements for LLM in Taxation Law.