Hi, i'm looking to swap my 2008 Sprinter 646 engine. I did that once and put second hand engine from vito van. Only needing to change cover and sump. As it's 9 years already when euro 5 was introduced it is really hard to find low miles sprinter or vito euro 4 engine. Would any om646 engine be the same with just minor differences like head cover or sump? Are there any online parts catalog to see the blocks, cylinder heads part numbers?