Citing PDF image copies of England GRO birth and death registrations

I recently took advantage of the cost savings by ordering PDF rather than certified copies of birth and death registrations from the UK General Register Office. How do I cite them?

This is my attempt to use the 3-layer system: What I saw--a digital image of a birth entry on the UK Passport website; Where it came from--the General Register Office; Where they got it--birth register from the Wirral Union registration district. Does this citation work?

England, General Register Office, registration of birth, entry for Joseph Wheeler Smith, born Birkenhead, 8 September 1847, digital image; imaged at “General Register Office,” database with images, HM Passport Office (https://www.gro.gov.uk : accessed 30 April 2024); citing Wirral Union registration district, register of births, vol. 19, p. 302, 1847 September quarter, entry 99; PDF electronic and physical copies of the entry privately held by xyzzy, street address, city, state, zip code.