Technical Spalding BDI- Ignition

I picked up this at a estate sale. The owner (over 80 years old) was in to Model T hot rods for years. When he p***ed away the family sold off all his old car stuff. I picked up the Spalding BDI ignition unit and have not been able to an information about it or what it will fit. All my internet searches have given me information about the company, but nothing on this unit. Thanks in advance for any help, Daryl

 

I remember reading about them when they first came out in the late 60s. It was one of the first electronic ignitions. It used a light and a photoelectric cell in place of points, if I recall correctly. Haven't thought of them in 50 years.

 

Used on the 4 cylinder Offy engine in the 70's.

 

late '60's, as i recall. uses a light to fire (laser, maybe?), thus the name, "beady eye"!