car making serious grinding noise when putting into reverse

What is your question?

My automatic 95 DelSol has been problem free until today. 218,000 miles. I start it up today and go to put it in reverse and I get quite a serious sounding grinding noise and immediately shut it off. I do not see any leaks under it and do not smell anything burning, etc. Could this mean transmission issues? I've been commuting with it 85 miles every day without any issues until now. No shifting or acceleration issues, nothing noticeable that would warn of this. Still great on gas and I get the oil changed as needed, synthetic only. My mechanic wants me to have it towed to his shop locally but I won't even be able to push it out of the garage. Can I shift it into neutral without turning it on? Thank you!

What makes this problem better or worse?

when putting it into reverse

How long has your 1995 Honda Civic del Sol had this problem?

just started