Proceed according to engine type: for 4-cylinder petrol engines, remove the cylinder head and sump; for 6-cylinder petrol engines, remove the cylinder head, sump, and oil pump; for diesel engines, remove the cylinder head, sump, oil pump, and, if applicable, the oil baffle plate. If a pronounced wear ridge is present at the top of any bore, it may need to be removed with a scraper or ridge reamer to prevent piston damage during removal, as such a ridge indicates excessive wear. Check the connecting rods and big-end caps for identification marks, ensuring both are marked with the cylinder number on the inlet manifold side, noting that No 1 cylinder is at the timing chain end. If no marks are present, use a hammer and centre-punch to mark each connecting rod and big-end bearing cap with its respective cylinder number on the flat machined surface, taking care to note the side of the connecting rods where the marks are made. Also, check the piston crowns for a direction marking, with an arrow on each crown pointing towards the timing chain end; if obscured by carbon build-up, clean the piston crown to check for a mark, and if the arrow has worn off, make a suitable mark using a scriber without deeply scoring the crown. Turn the crankshaft to bring the appropriate pistons to bottom dead centre, then unscrew the bolts from the No 1 piston big-end bearing cap, remove the cap, and recover the bottom half bearing shell, taping them together if they are to be reused. Use a hammer handle to push the piston up through the bore and remove it from the top of the cylinder block, taking care not to damage any piston cooling oil spray jets. Recover the bearing shell and tape it to the connecting rod for safekeeping, then loosely refit the big-end cap to the connecting rod and secure it with bolts to maintain the correct order of components. If applicable, remove the No 4 piston assembly for 4-cylinder engines or the No 6 piston assembly for 6-cylinder engines in the same manner, and turn the crankshaft as necessary to bring the remaining pistons to bottom dead centre for removal.