Neil,
Although I don't have any proof, I believe the Manchester Dineleys are descended from Thomas Dineley, born 1624 in Clitheroe! Naming patterns would suggest this and, like you say, it is the strongest likelyhood.
I can only go back to about 1802 with any certainty, when Thomas Dineley (my 3rd G.Grandfather) was born in Manchester. It is likely his parents were Robert Dineley and Elizabeth Bagshaw but I have yet to prove this beyond reasonable doubt!
Thomas Dineley married Alice Crawshaw (about 1823) and had 8 children, as far as I know. I know he later married two other people and died in Buxton in 1874. One of his sons was Edwin Dineley, born about 1824, who came to Edinburgh in 1860/1, married a local lass and settled here.
Hope this helps a little!