From the "In the hot seat" thread on P&B.
"08/05/08 - Dick Campbell (Forfar Athletic)
30/12/10 - Stuart McCall (Motherwell)
16/05/11 - Ally McCoist (Rangers)
18/05/11 - Derek Adams (Ross County)
07/10/11 - Jim McInally (Peterhead)
04/12/11 - Greig McDonald (Stirling Albion) (caretaker initially, officially confirmed 21/01/12)
21/03/12 - Jim Jefferies (Dunfermline Athletic)
15/05/12 - Mark Roberts (Ayr United)
03/07/12 - Grant Murray (Raith Rovers)
09/10/12 - Ray McKinnon (Brechin City)
22/10/12 - Stephen Aitken (Stranraer) (caretaker initially, officially confirmed 27/10/12)
22/11/12 - Ian Murray (Dumbarton)
13/01/13 - Jim Chapman (Annan Athletic)
30/01/13 - Jackie McNamara (Dundee United)
30/01/13 - Alan Archibald (Partick Thistle) (caretaker initially, officially confirmed 22/03/13)
03/04/13 - Alex Neil (Hamilton Academical) (caretaker initially, officially confirmed 24/05/13)"
Either joint 2nd if including the caretaker stint, or 3rd.