This is quite nerve wrecking but I am on a mission…this is what happened last night:
I had them in the pen area for about 10 min. At first they were calm then Thumper came her way, of course to mount and she was again not having any of that, so I put a stop to the aggressivness by sitting down and petting both of them 
I then brought in their greens and they ate on opposite sides while glacing at eachother. After a while, they started to get near eachother again (peaches ears were not in attack mode but she looked like she was going to lunge) and I started petting them and they switched places and started to eat where the other was eating before. When they finished, I gave them each a treat and more pets and then took Peaches out first to put her in her cage and am giving Thumps some free time before I give Peaches some free time.
They also spent "time" together when Thumper is out. He was hanging out by her cage. They ran around (him outside, her in) around the cage and occasionally groomed and sometimes nipped (not hard though, I was watching). They were both doing body shiver and head flick type motions and Peaches just flopped to the floor a couple of times (quite funny to see).
I’m sure that if I left them on their own, Peaches would most likely attack Thumps, especially when he tries to mount her so I am far from that, but I think that it is not going too bad. I am trying to end all meetings on a good note and think that I might be doing a car ride sometime in the near future.