Glad to help Luis Carlos.
Andy, the rod is to compress the oleo, and is fixed via the door to ensure this - as the gear leg swings up through the arc whilst retracting, the leg is prevented from 'dropping', and the oleo 'shortened'. Without the rod, the extension would drop under gravity, once free of 'load,' and the gear leg, oleo, yoke and wheel would foul the wheel bay inner wall. One of my books describes the reason for the rod, and there's a drawing and explanation also, in the 'Squadron Signal' book, one of the images I was wanting to attach but couldn't.
The landing gear needed to be the height it is in order to allow clearance for the prop, when the aircraft's tail is up during take-off or landing, but it also needed to be attached at a certain point, rather than further outboard, which meant a way of shortening the gear, as it retracted, was required in order for the complete assembly to fit within the available space, as the wheel bay section of the well couldn't be moved further towards the center line, due to the supercharger ducting and other fittings within the fuselage.
Note that, in the photos I posted of the Duxford aircraft, the oleos are compressed ( the torque links are almost totally closed together), something I hadn't noticed until now, which explains why I've always thought the 'sit' of the museum's example looked slightly odd !
The choice of the yellow zinc chromate is more in line with what is normally seen on wartime P-47's. The Interior Green of the Duxford example is, I assume, a result of the restoration and, unless the restoration team had evidence to the contrary, is an unusual 'error', if it can be called that, as both the IWM and RAFM restorers are meticulous, and normally get things absolutely authentic. Of course, the green might also be authentic for a particular point in time, possibly applied to later-production aircraft, rather than the 'quick-build' application of just the ZC primer coat.