Outer Limits 4x4 Board

Hi i have a hj75 and am looking at buying a set of track assasin cv's but at the moment im just going to take a spare set with me when 4wding. My question is are all 75 series cv's the same? eg hi pinion front diff same a early 75 front diff? same as 60 series? same as 80 series?

I have a 91 model with a hi pinion front diff.