Poor Man’a Covered Calls

Hi r/options, I’m looking for help to learn and grow. I have \~1000 LEAPS I purchased almost a year ago that are well in the money now, and want to sell “covered” calls against these LEAPS. I recently converted to a margin account to be able to sell those calls against my LEAPS. I own the LEAPS outright as I bought them 100% with cash. Given each call I sell will generate premium, and I already own the LEAPS outright, how can I calculate how much “margin” will be tapped? Given my margin buying power is a fraction of my account balance (my LEAPS don’t count as margin-able assets), does that mean then I won’t be able to sell PMCC against 100% of my LEAPS? Thanks in advance.