Timeline of Smokestacks on the DSP&P?

[Reopen the Alpine Tunnel!!]

I'm trying to figure out the approximate timeline of the DSP&P/DL&G in when they changed the smokestacks on their locomotives, e.g. the Nesmith design, Congdon, Diamond, etc. I know that at first, they used either balloon/Nesmith stacks, as well as the diamond stack for some of the Mason Bogies, then they switched to Congdon around 1884. But I am not entirely sure about when they dropped the Congdon design for diamond stacks, though I know it was after 1885, as well as when they adopted the McConnell (pancake) design on the DL&G. Anyone else here have a more approximate knowledge or lead on the subject?

[Chris Walker]

Mal Ferrell's "The South Park Line" has a whole page dedicated to this, with dates and observance's; pg205.