Fat PS2 laser interchangeability

Hey
So I'm repairing a PS2 for someone and they requested that I install a new laser so I ordered one from china on ebay.
It arrived the other day but they sent the wrong one, the ps2 in question has an HD7 laser and the one which arrived is a KHS-400r the seller wants me to return it to china (at my expense, postage which would cost almost as much as the laser itself)
I think I read somewhere on the internet that the two were interchangeable but I'm reluctant to put it in the machine unless I'm certain, so any clairfication would be helpful

 

From what I know, you can use a HD7 and KHS-400R laser interchangeably. It's only when you want to get a console (Above v5) that has a KHS-400C to use a KHS-400R that you need to use the lenschanger program to reprogram the MECHACON.

My SCPH-39006 has a Sanyo HD7, which is usually found in v9 consoles and up. So it must be possible.

 

Yeah, i also think HD7 and 400R are compatible.

If I were you I would run Lenschanger.elf anyway, but I don't know if that is a waste of time or not.