An online tree - right or wrong - has:
John ELLIS
Born 4 Mar 1764 Dawley Magna, Shropshire
Died 17 Dec 1826, Wellington, Shropshire
(aged 62 if born 1764)Married Catherine ONIONS on 27 Feb 1786, Wellington, Shropshire
Catherine died 1854 (she's on the 1841 & 1851 Census
Parents: Married 5 June 1763 Wellington
John ELLIS : Born ? - Died 1792 Wellington
Susannah WILSON: Born abt 1739, Condover, Shropshire - Died 1821 Lawley Bank, Shropshire
Siblings:
Thomas b 1766
Susannah 1768
John b 1771
It still somewhat troubles me though, that your Thomas ELLIS was illiterate and his witness John ELLIS apparently was not - if these were brothers?
The John ELLIS of address 'The Rock', Wellington who died Wellington on 17 Dec 1826 (the writing of his name of the burial register, looks like his own signature,

) is reported to be age 68, indicating a birth of around 1758.
Cheers
AMBLY