what an interesting thread! I've always loved rams, and had actually read this thread just a few days before I bought a pair for my 90G. I'm glad I had, because I recognized the signs that the female was getting ready to spawn, from what you'd written.
I put the pair in the tank on Tuesday evening, and they spawned last night, just over 48hours later. As mentioned, it's a 90G tank. Substrate is black sand, there's a piece of driftwood, a variety of rock, including some flat ones, and a couple silk plants. Tankmates are 6 angels, 3 platies, 6 glowlights, and a bushynose pleco. The rams spent the first part of yesterday evening meticulously "cleaning" a leaf on the silk plant, and guarding the area around it from all the other fish. After a couple hours of this, the female started laying eggs. She didn't lay many, I'd say between 20 and 40 over a half hour period. As she laid them, the male went behind her, eating them, rather than fertilizing. Could be he was thinking, "hey lady, I don't want 300 kids!" lol. Once she was done with the egg laying (and he with eating them), things went back to normal, and they were no longer guarding the plant, although they're still always together.
I wasn't planning on breeding, so it really doesn't matter to me if they have a successful spawn. I just thought it was VERY cool to see! I got the rams simply because I'm a huge dwarf cichlid fan, and I think GBR are about the prettiest fresh water fish there are.