A fellow from Benzworld did the troubleshooting and ended up at the tee fitting of the junction near the rear axle and located his bleed-down leak there. So in that case it was not a solenoid, and I suspect in mine it will either be here or at the manifold in the engine compartment..Currently getting a slow bleed down only on the left rear as shared..This afternoon when its warmer I will get after it! And the mechanics make plenty without our funds helping them, these forums are a great example of free, supportive and voluntary community which benefits us all.
Im kind of a 'lefty' and I enjoy sharing the idea of co-op work like the Amish barn raising that is practiced in traditional cultures world wide, but we call it 'socialist' and outlaw its mechanisms. (no offense to good hearted conservatives)