Transistors which leg is the Emitter?

To all the Real Electronic Gurus out in AVSA land,  I need some help .

I am busy restoring a Quad 303 power amp and have been guided by many Googled accounts of which transistors to use as replacements for the original parts used.
I have gone to such lengths to obtain the "better" transistors etc but I now find myself with the problem that these new transistors are different shapes and do not show which leg is base emitter or collecter. I have been able to test and ascertain which leg is the base but still don't know how to locate the emitter etc.The transistors I have are TO5's They are like a small cylinder with one side flattened and the three legs come out the bottom of this cylinder.
According to a spec sheet I have located on Google, there are three different types of these shapes of transistor and each type has a different position of base emitter and collector.
I have noticed that on top of the transistor there is a small "-" mark and it is not always on the same side. Some times it's on the left side sometimes on the right side. Is this mark showing collector or emitter or what.
I have also been able to identify a PNP from an NPN transistor with my meter.
Thanks in advance for any help I can get from the "Brains Trust"