first time MTM filer. Have 30000 Capital Loss Carryover. Will my gain this year offer any of the previous loss? if Yes, where do I enter that carryover loss?

Hi, trying to decide if I should do MTM this year or next. I have $30K Capital Loss carryover. if filing without MTM, my trading gain this year will offset the entire amount.

I have done the MTM election and can file as trade tax status. But if I use form 4797 for my trades, will I still be able to offset the previous trading (Capital) loss? if I can, where will this loss be entered? on Schedule C?

Thanks for any help you can provide.