This is one of those total PITA subjects, because there is possibly more than one answer.
If you parse the PP catalogue, and the linked Speed Bleeder website above, you'll come away believing that you need two different types for all '75-'89 front and rears.
But!, on my '84 911 both F/R are serviced by the SB8125LL (
https://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=PEL-SB8125LL). I had to make a decision and bought two sets for my project, and fortunately both fit F/R without issue. Now, technically, the Carrera brakes are termed Wide A and Wide M, (I dont think they changed the bleeder as part of the design) but PP doesn't necessarily catalogue with that degree of specificity, and neither does the Speed Bleeder website, grr.