Very interesting - Here's the specifics of party alternation I looked up-
Whigs - 1721-1762, starting with Walpole
Tories - 1762-1763, Bute
Whigs - 1763-1770, starting with Grenville
Tories - 1770-1782, North
Whigs - 1782-1783 - Rockingham, Shelburne, Portland
Tories -...