A new problem I discovered with my setup is the Clippard solenoid runs so hot I am not sure if it would even be a good idea to connect directly to the regulator? It may not be a problem with the heat need another opinion on that .
You will need some adapters to connect from the regulator to the solenoid anyway, so the solenoid will not be connected directly to the regulator.
Many people do this, and it seems OK; though you are correct in mentioning that the Clippard solenoid does run quite warm.
Another issue is with the addition of the clippard solenoid + new needle valve or even the current stock needle valve I would have a long extension of metal hanging out to the side. Probably not that bad, but for me I do not have a standard cabinet to store all my equipment on my set up.
I guess I could find an elbow & a straight to make it work.
That's the way to go. If you want to save space, use elbows.