I have studied all Thomases with baptismal records in Somerset and Devon, from 1760 to 1774.
My Thomas married Frances Broadbeard (bp. 1779, parents John and Elizabeth) in North Petherton in 1798 and they had 7 children:
John, Elizabeth, Mary, Thomas, Sarah, James and William, so I have tried looking at naming patterns too.
Apart from the age, the Thomas baptised 1760 in N. Petherton seemed a good option, but absolutely no-one was ever called Catherine (until my sister 6 generations later - and that was because of the film "Wuthering Heights" that appeared shortly before her birth !!)
In this case, Thomas would have been 81 already in 1841 (rounded down to 75?), and at death in 1853 (I have the certificate) 93, not 89 (but perhaps his son, the informant, didn't know). At marriage he would have been 38 with the last child born when he was 61. All possible, but...
There are not many Thomases baptised in Somerset in the right period:
1760 Thomas son of John and Catherine in North Petherton
1772 Thomas son of Thomas and Mary in Timberscombe
1768 Thomas son of William and Sarah in Wiveliscombe
1774 Thomas son of Samuel and Catherine in Brompton Ralph
1769 Thomas son of John in Rose Ash, Devon
The Thomas of Timberscombe really isn't old enough considering the ages, even making allowances, at the censuses and death, nor the one at Brompton Ralph.
Which leaves the ones in Wiveliscombe and Rose Ash.
The Wivvy Thomas has an acceptable naming pattern (John and Elizabeth = maternal grandparents, Sarah = paternal grandmother, Thomas = father, James = paternal uncle, William = paternal grandfather [though surely pat. grandfather before paternal uncle?] - except for Mary.
I've been looking at John who married Anne Lyddon in Rose Ash in 1768 - no-one named Anne in the descendance either! But the ages are closer and perhaps Thomas thought he was older than he was !!!
So what else can I try? There are no wills - they were labourers, though at marriage Thomas is shown as a husbandman.
Can I find a connection somehow between the 1760 baptism in N. Petherton and Stoodleigh/Studley? Or the Wivvy baptism and Stoodleigh/Studley?
Probably a brick wall I'll never break down...
Margaret