STC or advice for running a cabin power extension cord

[FlySafe]

Hi All, looking for advice on best method to get an external power cord connection inside the cabin for the winter heater (hornet).  Plane (M20C 74)  on ramp so ideally would have a permanently placed external connector as on the engine heater to allow easy connection to an power extension  cord and then an internal connector on the inside for the heater hook up.  I hate having to run the heater cord through the small pilot side access window due to dust and moisture getting in plane even with cover on plane.  Thanks in advance for your shared wisdom.

Best,

kurt

[Z W]

I think you may want something like the Tanis cabin heater:

https://www.gallagheraviationllc.com/tanis.html

Never seen it installed, but from what I understand, you plug in one plug in the oil filler door and it runs both the engine block heater and the cabin heater.

[smwash02]

I've got a preheater that has a plug in the oil door, but that would require penetrating the firewall.

Took me a minute, but finally found the thread. This idea from @squeaky.stow is what I'd do.

[FlySafe]

Thank you all, great ideas!