No idea.....
I just copied and pasted that from the Angel Owners website. Sounded like I knew what I was talking about though, didn't it...!
You might want to check on there. I just did a search for 'Mini Reg Mod' and came up with this.
Here's another pasting....
all you have to do is remove one spring from the stack in order for it to work with a HP tank. the order is up, down, up, down, up, down.()()()
for a HP tank, it should look like this. ()()(
I don't think it really matters which end you take it from.