In 1967 Simon & Garfunkel recorded a show for ITV which was broadcast in 2 parts May 2nd and 9th 1967 in the Northern parts of the UK:
It seems to have been an “informal concert”
1967: ITV – UK TV Show
In 1967 Simon & Garfunkel recorded a show for ITV which was broadcast in 2 parts May 2nd and 9th 1967 in the Northern parts of the UK:
It seems to have been an “informal concert”
Paul Simon - 'Time it was...it was' 
Sounds like the 1967 Granada TV special recorded in Manchester. Available in many videos on YouTube.
yes that could be the one. Thanks for heads-up.
It was recorded on March 17th, 1967.
https://missingepisodes.proboards.com/thread/5721