I don't remember saying anything about them needing to be vertical... I personally don't remember having had any issues with solenoid mounting direction....

Just for the record, I do not feel that a Tial BOV is required... With really high boost maybe some sort of 50/50 is better, but there are WAY too many cars running high boost with things other than Tials and no issues. We've got a Red running 28 psi every day on a HKS SSQ...

SS