Hi Allen,
Before talking about you purchasing rear shocks, may I suggest that instead of putting progressive springs in your forks with the intimidators, you save your money and just put intimidators in.
I have at a bit of experience with modifying my suspension and in my opinion, the intimidators work much better with the oem springs. I know it probably doesn't sound feasible but I have a set of progressive springs in my garage after using them with intimidators and then reverting back to oem's just for curiosity reasons. Without doubt the intims and the front work much better with the oem springs and considering they were developed to work best this way, you could save yourself a lot of time, effort and cost. It's your call but that's my experience.
Regarding the rear shocks, again it's my experience i really don't think you could go past Hagon Nitros. There are others on here who I know will agree with me including Eddy from "Fast Eddy Sports" who did an extensive comparison between them and the Progressives and now he has them on his Thunderbird.
These are simply suggestions from people who have been where you are now except we (I and others) had to do it the longer and harder way.

Cheers
Stacka