One suggestion is to see about getting a guide, who will take you in a better vehicle. Someone with a high clearance SUV, Pick-up, or ATV perhaps. With a pick-up you can get back to Big Horn, and a few places between big Horn and Sublette. We shot outside Antonito, then made it into Big Horn, and Sublette, and overlooking the canyon off the Osier road. That somewhat main road is not so bad for most vehicles. The problem we had was east of Big Horn on some lava rock roads that took us nowhere. I found the experience at Big Horn wye to be a good one. I shot video for about 5 minutes as you can see it in the distance for quite some time, and working toward Big Horn. Then you just double back toward Sublette, and eventually toward Osier. But if you aren't comfortable doing it with your car, then don't! Its not worth a major repair bill. Also consider that sometime in the future you should spend the cash to do a photo charter. $300-$600 for a charter could be less than an auto repair bill. The beauty of the photo charters is 3 fold. (1) A special train generally lettered historically, and with historic equipment. (2) They get you into remote locations that you might not normally be able to access, and (3) They work the engines and put on a good sight and sound show!
Most of the better shots I have in the area from Antonito to Cumbres are from 2-3 days of charters I was on.
Also consider riding the second day, and spending time in a different part of the train. I look shooting pictures and watching the scenery from about the 3rd coach platform behind the engine. Also spend some time on the platform behind the tender, especially westbound when working. Then on the third day you can get it leaving Antonito, go to Chama and check things out, then drive to Durango for your next D&S ride. As others have said running out of Rockwood there is not much in the way of photo ops for you when not riding. You could always do a bunch of hiking with Olaf!!! Main thing is to have a good time and enjoy the steam while you can! It beats staying home but be safe!
Greg