If you've taken the clonazepam I'd also say save the LSD for another time. Personally I feel like eating benzos before a trip doesn't put you in the right head space and the only time you should do this if you're uneasy with the come up. Even then I'd say try to tough through it because once it does hit you're on for a long ride and you want to make the most of it.
As far as alcohol causing bad trips, I don't necessarily agree but everyone's different. I've been pretty drunk, dosed, and then when I started tripping all the effects of the alcohol wear off. I also find while tripping I can drink copious amounts and it has no different effect besides when I'm coming down. The LSD for me always overpowers the alcohol.
If you've been drinking and taking benzos, you're already setting yourself up to black out so I'd really avoid the ambien. Have you taken it before, and have you heard some of the stories of people doing crazy shit while blacked out from ambien? A lot of stories are incredibly bizarre, but I guess when you do black out stuff like that happens. I know I wouldn't want to put myself in that situation.
As far as adding the LSD though, no it's not a dangerous interaction but for the sake of HR I wouldn't be mixing those prescription drugs with alcohol. Really, a lot of bad stuff can happen and if you're lucky enough for something not to go wrong your chances of remembering anything is slim. Pointless and it's not worth it.
EDIT: When I'm talking about people doing crazy things on ambien, look what happened to this member a few years back. When I think of ambien, this story is the first thing that comes to mind.
http://www.bluelight.ru/vb/threads/407727-Help-I-ve-made-a-big-mistake