I agree. One thing on exhaust staining - if it's black, then the engine is running very rich, or burning a lot of oil, or damaged! This is evident in pics of belly-landed aircraft, where the staining can look heavy due to engine damage, compared to the same aircraft seen before crash-landing. Also, in pics of late-war Luftwaffe aircraft, over-run by the Allies, it may be that the engine has been run 'dry' (of oil) in a deliberate act to seize the engine, denying the enemy of a 'prize'. This would cause very heavy staining of course, the latter being easily confused, in some B&W pics, with shadow areas or heavy mottle.
Looks good on yours so far though.