They had a couple, portable 4 part/line Block & Tackles. The B&T was rigged to a small Cleat, inboard, below Cap Rail. Timber Painter Line was hooked to lower Block, slack taken out, and the Timber pulled up.
Several places had small cleats, several places had holes in uprights, where a Shackle could be used.
Each Timber had a Cleat or Shackle it hung from, afixed to inboard side of Bulwark.. The B&T, would be rigged to a cleat/shackle a couple of Timbers back or forward, of the one being lifted.
Because the B&T was aft from were Timbers were hung, they could pretty well pull a Timber up to the Cap Rail, then just muscle it over the Cap Rail, onto the Deck.
The Timbers would lay on the Deck, up against Inboard Side of Bulwarks.
To put them back down, same thing in reverse; B&T to get Timber back up and close to Cap Rail, then just muscle over Cap Rail and splash down to water.
He reall emphasized it was lots of muscle work, so preference was to just let them hang in water, unless pulling a Barge or Dredge on a long Tow..