SQL convert vertical to horizontal

IF OBJECT_ID('tempdb..#Parts', 'U') IS NOT NULL DROP TABLE #Parts

CREATE TABLE #Parts

(

ID int,

ID2 int,

PartNo varchar(10)

)

SET NOCOUNT ON

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 23921, 'DENT')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 26145, 'PLGD')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 26145, 'PRRP')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 26145, 'SIST')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 57290, 'PRMD')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 57290, 'abc')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 57290, 'def')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 57290, 'ghi')

INSERT INTO #Parts (ID, ID2, PartNo) Values (75, 57290, 'jkl')

SET NOCOUNT OFF

SELECT * FROM #Parts

SELECT ID, ID2,

Max((Case When RowNumber = 1 Then PartNo Else '' End)) AS Part1,

Max((Case When RowNumber = 2 Then PartNo Else '' End)) AS Part2,

Max((Case When RowNumber = 3 Then PartNo Else '' End)) AS Part3,

Max((Case When RowNumber = 4 Then PartNo Else '' End)) AS Part4

FROM

(

SELECT ID, ID2, PartNo,

ROW_NUMBER() OVER(PARTITION BY ID, ID2 ORDER BY PartNo ASC) AS RowNumber

FROM #Parts

) AS tbl

GROUP BY ID, ID2