Actually a blog is where people post their opinion/ramblings on a subject of their choice in the hops that the wider internet community will leave comments and link to them most of the time in the hopes of making money.
Forums are places the people are able to open threads to speak the mind or ask questions and then other forum members are able to discuss and speak their own mind(within the rules of the forum). It quite frankly scares me to think you would wan't to follow instructions from random people on the internet when dealing with you're pride and joy(it's an e36 after all). You're DIY'ing, have a go...try different things and problem solve.
You tell me you have installed plasma gauges before so in your own real life experience you have seen something along the lines of this pic;
http://www.bmwe36blog.com/image-viewer. ... bmw-e36-12All thats left to do from there is remove the clear plastic from the black piece in the top of the picture. If you have had it out before I don't think its beyond reasonable expectations that you have a good enough head on your shoulder to enable you to pop two pieces of plastic apart.
All but one of the 5~ e36 clusters I have dealt with were able to just be popped off. The other was similar to what AngeloViveros said. In which case you could have come back and said "shit it looks like is glued." If it glued you're SOOL unless you're comfortable with taking up a screw driver and wiggling and trying to crack the glue... or even dissolve it with something? There may very well be a better way but as you haven't found it I'll assume it doesn't exist or at least isn't documented.
I assume it was an eBay buy? Most sellers who stock cluster bezels have reasonable PDF instructions... did you get them/ask for them?