How do you set the timing marks to the chain on a 2003 4.2liter Oldsmobile bravada?

To set the timing marks on a 2003 4.2-liter Oldsmobile Bravada, first ensure the engine is at top dead center (TDC) on the compression stroke for cylinder one. Align the timing mark on the crankshaft pulley with the timing tab on the engine block. Next, verify that the camshaft marks are also aligned; the mark on the camshaft gear should be facing the mark on the engine. Finally, ensure the timing chain is properly tensioned before reassembling any components.