Emerson's Brooklands ABC Sopwith - a question?

-Just catching up with the Forum.
Most of the most recent queries about Bob Thomas' racer can be answered by inspection of the photo in Association Newsletter no. 1004.
Its oil pump was a Best and Lloyd (as in the Norton photo appearing in regabyneil's piece above). I can confirm that the inlet manifold was standard, but the (separate) exhaust pipes were of slightly larger diameter tube, that were welded-on over the original, flanged stubs.
I've seen the supplementary rocker return springs on other machines, suggesting that they could have been factory-originals.
Hope that this clarifies the Bob Thomas queries!