See Castle Street East 1 to 15 &c in London Addresses dataset
No 8 Castle St East Land Tax 1784 Thomas Gibson / Harris's List 1788 Miss Br-wn 1789 Miss B-ks
The Covent Garden Ladies were in the gap for which we have no Land Tax Records 1785-1790. Thomas Gibson = 11.5.1776 St James Piccadilly to Lydia Louise Jullion / London Consistory Court will dated 13.8.1785 of Thomas Gibson builder of St Marylebone with brother James erecting building on corner of Weymouth St & Portland Pl mortgaged to John Elwes Esq, wife Louisa Lydia proved 17.9.1785 / Louisa Lydia Gibson widow otp = 27.5.1790 St Marylebone by lic John Fraser wid otp