Removing the bhk preamp top

I noticed a screw was loose on the back and tried tightening it and the nut fell off. It’s right behind the ac input where it needs to go. I’ll need to remove the whole top cover of the preamp but not sure how to remove it.

Thank you hiendmmoe for asking. I also was wondering how one might open the black top cover without marring it?

If there is anyone who knows can they reply please?

Disconnect everything to the preamp and flip it over on a towel and remove the 4 dark coloured screws on the bottom. Flip it back over and remove the tube access panel gently use your fingers to lift the black cover.

Thanks watchdog for the quick reply. You mentioned the 4 ‘dark colored’ screws on the bottom! I have not turned mine over so I was wondering if they might be the screws that also hold the 4 rubber feet?

Can anyone supply a picture of said underneath/bottom of the BHK Preamp?

No, they aren’t the same.

Ok, thanks.
The quest continues.
At lest now I know how the black cover is held in and that is a very big help!