I'm using regular reinforced stone, clear reinforced glass, and regular valves in my setup. I've taken two screenshots to show how I have the fusion reactor set up in my creative test world.

IC2 Classic 2.0.1
Forge 43.1.47

Am I being an idiot, am I supposed to be using some other valve block, or is there something ese I need to do before the fusion reactor works properly?

Thank you for your time, and I'm sorry if this is the wrong place to ask this.

Top Left of of the Side you place it on. the wiki says that. But its a general rule.
Facing also matters.

Also make sure you looking at the side you also place it on. Since the placement is based on your looking direction.

Yeah, I'm an idiot. Thank you for your help, and thank you for making an amazing mod!

No Problem @levicc00123