Max instrument depth on panel

Both my gyros were old and when I priced the cost of overhaul vs a AV-30, the AV was cheaper, plus I got rid of 13-16lbs of vacuum system.

appreciate the advice ... looks like the safe thing to do is a little exploratory look behind the panel

Thanks Matt, the AV-30 was the path I'm headed down. Before I pulled the trigger on that I wanted to take a quick look at others like the Garmin GI 275 ...just to make sure I don't have any regrets in the future.

Regardless I plan to relieve the airplane of the vacuum system.

Depending on what instruments you are overhauling, if it is a Attitude and DG, I would replace them with a AV-30 and remove the vacuum system.

You really just need to measure at the location you want to install the instrument. The header tank has overflow and supply tubes that get in the way, and don't forget to allow room for the connections of tubes and wires on the back of the instrument. If you try to extend under the tank, you start getting in the way of the control column. I found every instrument to be a custom fit, a lot of nesting.

Understand the header tank limits instruments to a depth of about 6" at the top of the panel.  Where can I find the exact measurements (depth and how low on the panel the fuel tank extends).  I'm looking to refurbish instruments but am unclear what exactly can fit.

Thanks in advance!