Find the number of ways the digit 0,1,2 and 3 can be permuted to give rise to a number greater than 2000

Please, I need explanatory answer

first digit 2 or 3, two ways

second 0 ,1,2 or 3 four ways
third Four ways
fourth Four ways
2 * 4 * 4 * 4 = 2 * 4^4 = 2 * 256 = 512
HOWEVER
If I can only use digit once in the number
First 2 or 3, say use 2 ( 2 choices)
second other ( say 3) , 0,1, (3 choices) say use 3
third 0 or 1 (2 choices)
left with one choice
so
2 * 3 * 2 * 1 = 12 ways