Here's a comparison of both models.
I had been using the Heat Pipe version inside a small camera/cell phone pouch on my belt since it was too nice to modify, but for this one I wanted to have it visible, like in the reference pics.
At the suggestion of Brandon (Donkey8012), I removed the belt clip from an old tape measure.
When I drilled the hole through the casing, the bit would only go a very shallow distance in, and then there was this scary sizzling noise. I thought at first it was emanating from my drill, and I thought the motor had caught on fire or something... then I realized it was coming from the Minirad, and that was worse, as it made me fear for a moment that I was receiving a dose of radiation! Yikes!
It subsided after a few moments, and I realized it was air escaping and hissing out through the hole.
According to the description of the prop found here, http://www.gbfans.com/equipment/other/gamma-rate-meter/, the Minirad employs "a pressurized ion chamber"... I don't think mine is pressurized anymore!
Shrug, that must've been how they made the prop, and the same thing must have happened to the one Harold Ramis used, and he seems to be doing okay thirty years on, so best not to worry about it.
Ready for action... except...
... it doesn't have its instruction on the battery cover. Take a look at the reference pic on the Equipment pages of a more pristine Jordan Electronics Minirad...
Unfortunately, I can't see the actual prop close enough in the reference pics I'm checking to tell if Ramis' sample had the lettering. After all, Egon could have tinkered with the real device to make it take supernatural readings, and could have altered the casing instructions as well.
Speaking of reference pics, I would LOVE to know where this photo came from. Can't we find it bigger anywhere?
I know the Minirad can be seen on the work table in the basement, so I do plan to watch the new Blu-Ray again and hope for the best.
In the end, I will probably add the instructions eventually. I thought about finding some REALLY SMALL rubdown letters, but ye gods would that be time-consuming.
It would be so much faster to type it up and print it onto clear label paper.
Of course, just when I got everything sized the way I wanted it against a 1:1 scan of the Minirad...
... that's when I remembered my printer was out of black ink. Wah wah waaaah.