Made the hour trip out to the GarrapataPark south of Carmel mid afternoon.
Clouds were a no-show, but I expected that from the forecast.
Here some pre & post sunset images with 10-stop applied to a few.
The cast doesn't look like a Lee Big stopper. Maybe a B+W or Hitech? I use the B+W ND110 and I usually just mess with the WB. Since you have the non filtered shot as a references you can also mess around with WB, sliders, etc to try and match it as close as possbile. Photoshop CS can be a good tool for that. Also sometimes I'll use one of the filters in Nik CEP4, which can be helpful.
As far as your shots I like #3 the best besides it being a litlte underexposed IMO. Some adjustments in curves/levels could help it too. If you have a cable release I would have tried a longer exposure, 60 sec, 120 sec or even longer.
I like the color cast... The 3rd image is gorgeous! Very inspiring.
Don't have Lee filters, but Cokin, Singh Ray and Heliopan. Heliopan (especially the Heliopan ND 3.0 = 10 stops) as well as some Cokins can cause heavy color cast (e.g., http://www.fotoblur.com/images/481985), but I have to admit, I sometimes like that effect a lot. Agree to Scott: I just play around as well with white balance, color and color temperature using the RAW converter (PS 5.1).
Volker
The 3rd image is gorgeous! Very inspiring.