The updated EFIS hardware came with a new Remote Compass Sensor. For some strange reason the newer model Remote Compass Sensor has a different pin-out on the connector, so I had to disassemble the connector to move two sockets to different spots on the connector. This would be a fairly easy job on the bench, but I had to do it way in the back of the fuselage, after crawling in head first. The connector was up at the top, but there wasn't enough room to lay on my back, so I had to lay on my side, and open it up, being careful to catch all 8 tiny screws, nuts and clips. Pulling and repositioning the pins wasn't too hard, and I managed to get it reassembled without losing any of the hardware.

I primed the Remote Compass Sensor bracket, bolted the sensor to it with non-magnetic brass hardware, then crawled back into the fuselage again to bolt it in place. It felt great to get that done.

Another shot of the mount.

Here you can see how far back in the fuselage the Remote Compass Sensor is mounted. It is two thirds of the way back from the bulkhead behind the rear seat to the leading edge of the horizontal stabilizer.

Last night I had a nagging worry, as I recalled that the sensor needed to be well aligned with the EFIS. I had this distant thought that I had discovered in the past that I needed a shim, and I had forgot to put it in. Today I reviewed my notes from when I fabricated the mount, and sure enough, I found I needed a shim to get the alignment correct. I reviewed the EFIS Installation Manual, and it said that the Remote Compass Sensor should be aligned within 0.2 degrees of the EFIS.

Tonight I installed my old instrument panel blank, and measured its vertical alignment with a digital level. I crawled back in the fuselage, and measured the alignment of the Remote Compass Sensor. Sure enough, it was tipped forward almost 4 degrees from what the EFIS was. Drat.

I removed the mounting bracket, which allowed me to discover that the low strength LockTite that I had used on the brass hardware didn't provide nearly as much locking power as I had expected. It is a good thing I discovered this, as I believe that the bolts would have eventually have vibrated loose.

I found a combination of washers and brass nuts that tipped the sensor the required amount. As near as I can measure, it should end up within 0.1 degrees of the EFIS. The trick now is to never measure it again. :)

Now I just need to buy some medium strength LockTite and then I can bolt the mount back in place. And I noted a chafing problem between one of the static system lines and the mount which I need to address. I will be overjoyed to finally be done with the Remote Compass Mount.