I'm assuming yours is 2-zone A/C which means it's the same as mine. If so, you have two options:
* with the solenoid - this is the top-end configuration - this divides the circuit into two smaller circuits - cabin, and engine block. Thanks to the valve, the hot coolant may flow either between webasto and the heater core in the cabin, or between heater core, webasto, and the engine block (both circuits). It is not possible to heat the engine block only - cabin is always included.
* without the solenoid - this allows coolant flowing through webasto, the heater core and the engine block always.
Even if your preferred config is the latter, I would recommend building the top-end config. With , you can still program the solenoid to always direct coolant to both circuits. If you ever change your mind, you can just change coding in Webasto controller, and you'll be able to heat the cabin first.
Here's what your game plan could be:
* source Webasto (Eberspacher) from Europe. It's not difficult. Find as complete set as possible. Make sure you're looking for a 2-zone config as the plumbing is different for a 4-zone
* optionally, but probably best way - purchase the wiring harness from Kufatec - I did it as well. I wouldn't do it again, as the harness is fairly simple, but I just wanted to reduce number of variables in this fairly complex project
* you're going to need some additional parts, like clamps, fasteners - most of it available in NA
* if you want a remote controller, you'll need to look on
ebay in Europe
* you will also need to run fuel line and install the pump - but I'd say that's easy
Once you start the project, I can give you some more detailed step by step. Substantial part of this project is planning and procurement
