However datewise I think we've skipped a generation, don't think the Thomas b 1743 would be the one fathering children 1797-1808 when he would be aged 54-65.
I have second thoughts about this.
If Thomas (christened 18 Sep 1743) was the father of William (married 27 Feb 1781), there would have been two weddings in 38 years - possible but tight. There would have to be a Thomas Green/ ? marriage around 1762.
However, if William (married 27 Feb 1781) is also the William (christened 24 Nov 1745) then
* he married age 35, and the witness could be Thomas his older brother aged 37
* first child Anna born 1782, William aged 37
* next child was John born 1790, William aged 45
* next child was Samuel born 1799, William aged 54
* last child William born 1801, William aged 56
* he died age 72
which is also within the bounds of possibility.
Thomas (christened 18 Sep 1743) could be the 1784 voter and a later marriage would make sense (if, indeed, he married). Could it be, for example:
[results for Name: thomas green, Event: Birth, Place: bedfordshire, Event Range: 1742-1744, Country:England]
09 Oct 1771 marriage between Thos Green and Eliz Mehew at Dean, Bedfordshire, when he was 28
[https://familysearch.org/pal:/MM9.1.1/N2SV-DBW]
I wonder if Elizabeth Green remarried. In 1748 she has a farm and three young children to look after: Ann(

, Thomas(5) and William(3). If she didn't remarry, would Thomas become head of the household on reaching age 21?
Can we find out when Thomas died and if he left a will?