Michel,
Well it depends...
...on how much later it is. A B29 has detachable cylinder heads, as did the Sports version of the EW. There are subtle differences to the castings, but nothing that would stop you from installing - I think - them onto an EW. That would hold true through the L3/H3 models, the A31/A32 models, and the Y1 model of 1934. In 1935, the 350cc dropped the gland nuts for the ports and adopted the flanged ports seen on the 250cc model of 1934. I am pretty sure you can still swap over the entire cylinder assembly of the 350cc Aero models on the EW crankcase, but obviously you would have to replace your intake manifold and exhaust system too.
Later tappet guides have a conical seat, they do not thread in like the EW. Not sure when the change over was. But the tappets and lash adjusters should be identical right to the end. Ditto valves and valve springs, but these are available new to LDMCC members. The timing gears and cams are generally the same, but they did make changes to the end of the end of the one cam wheel to provide a drive dog to the oil pump worm (the EW oil pump worm is integral with the crankshaft pinion nut.)
-Doug