Rotating/swapping front with rear Microphone Capsules

[RoadrunnerOZ]

Is it simple to add a switch on the U87, so that when in cardoid, you can switch to make the rear capsule as the front capsule?

Anyone know if its easy to swap the front head grill with the rear grill?

I'll do some further tests later on, as you are all correct, my initial test is flawed. It was better for me to spin the mic so that I get better consistency.

@RoadrunnerOZ, the issue with testing the mic with a speaker is that you are not capturing the behaviour of the mic when someone speaks and blows air onto the capsule which I believe is different to a speaker. I usually do your approach when testing at longer distances between sound source and mic.

Adding a switch is going to increase the length of the leads and also add capacitance from the body of the switch, this may or may not adversely affect the quality of the signal.
Edit: it would be really easy to do - the reversal capability would be in place for all settings as you could take the cables direct from the capsule to the switch - you would need to flip the backplate cables as paired with the diaphragm cables from what I see in the schematic.
I agree about the speaker test but for an A/B test this is only a method of direct comparison. With a really well trained vocalist who can mimic the same performance and have exactly the same mouth to mic position and distance each time, you could do it dynamically. The best way would be to double the vocal to an already recorded vocal - doing this twice - once for each diaphragm and then you could hear the difference between them with proximity effect in place.