AC Evaporator leak

I'm pretty sure my 2016 Tundra has a leaking evaporator. I've determined this by connecting my AC manifold gauges and confirming that there is no pressure in the system. I'm only able to pump the system down to about -10 inHG whereas I know my pump can go down to nearly -30. I put 12oz of refrigerant in the system and then with the AC system on full, my gas leak detector alerts when I stick it in the passenger side left vent. It also alerts on the passenger side right vent, but not as much as the left side. It also appears to happen more when I have the blend door set on dash vents only.

So with that troubleshooting done I'm pretty sure that I'm going to have to pull the dash out to replace the evaporator, but is there any other troubleshooting I should do to confirm that this is where the leak is and are there any other components of the system that it would be a good idea to replace in addition to the evaporator?

I consider myself a pretty capable DIY mechanic, but I've never completely removed the dash from a vehicle before, so any other tips would be appreciated. Thanks.

 

I've had this with different vehicle. Hopefully not too hard to remove dash. I'd probably take it to a AC repair place and have them diagnose, put die in there to see if it might be leaking some place else. I forgot what you call the valve but if it's only accessible when removing EC would replace that also. I'm no expert though. Keep us updated. Maybe someone else has more experience.

 

Expansion valve.