Aye Russell... thanks for comments, I bought the demountable beacon and when it came time to wire it up, there was a maze of wires that I couldn't make sense out of... so the body man who did the work was also a volunteer fireman and he volunteered to mount and hook up the light, the wail didn't work on the siren control unit, and the yelp quit the day I took it to the body shop. He took one of his own siren control units and installed it for me.
I wanted to be able to show it as a combination, but for day in day out driving through the community, I am surrounded by people have who don't remember the days combinations ruled the roost here (that service by funeral homes stopped here in October 1973) and so most see it as... Ghostbusters... I am supersensitive to people hollering Ghostbusters to something like this car... being the funeral home in the community - it will cause less stir and comment to just be seen as a neat old limousine style hearse.... I am also anxious to look at it's lines and design without the light on it...
(and, it will only fit in one of 3 garage doors with the light on, in that rear area, it is a TIGHT fit to get the 2 middle cars in, as I have 7 cars packed into a 6 car garage...)
In reference to the 184 Power light being used over a Beacon Ray, I think almost every 77-79 era I remember had a Beacon Ray on it, but the 184 Powerlight was out and getting to be used more widely at this point, in my hometown, the last thing I can remember having a Beacon Ray mounted was a 1971 Ford LTD police car (and that's BLUE in North Carolina)... so 1977 I was thinking of what was available and that a Powerlight could have been used on those models. )