This is the classic proportion. But if you find it too sweet, add more whiskey! I've seen recipes that are 4 parts scotch to one part Drambuie. I'm not a fan of blended scotch, so here I used laphroaigh, one of my favorite whiskeys, famously peaty. Use whatever scotch whiskey you prefer. Change it to Bourbon and it's a Rusty Bob!
Keyword cocktail, drambuie, rusty nail, scotch