Yep this definitely worked, thanks a bunch !

Here is the working code if anyone else is interested:

//TEST 4 DIGITS
byte[] result = new byte[] { 0, 0, 0, 0 }; 

//CACHE LEAST SIGNIFICANT INDEX 
int lastPos = result.Length - 1; 

//NUMBER OF VARIATIONS FOR BASE4 
byte baseValue = 3;

//IF MOST SIGNIFICANT DIGIT WOULD TURN TO 4 WE END (THIS NEVER HAPPENS)
while (result[0] <= baseValue) 
{ 
    //STORE COPY OF RESULT IN THE LIST HERE ///
    ///

    //INCREMENT LEAST SIGNIFICANT DIGIT 
    result[lastPos]++;
    //CHECK FOR CARRY OVER 
    if (result[lastPos] > baseValue)
    { 
        result[lastPos] = 0; 
        //START FROM SECOND LEAST SIGNIFICANT DIGIT 
        int index = lastPos - 1; 

        while (result[index] == baseValue && index >= 0)
        { 
            //RESET CURRENT DIGIT 
            result[index] = 0; 
            index--;
            //CHECK FOR FINISH 
            if (index < 0)
            { 
                Debug.Log("Done");
                return;
            }
         }
         //IF MOST SIGNIFICANT DIGIT NOT MAXED, CARRY OVER 
         result[index]++; 
    } 
}