Sorry to hear about the accidnet. Though the ride is important, if it is going to cause more damage to your shoulder, HOLD OFF....you can always do another MS ride this year.
Otherwise, good luck on the ride. I would say I would look for you, but there is only a 1 in 10000 chance to see you. <G>
I am now tapering down. Went and did hills in Huntsville last weekend - Did a hilly 102 miles on Saturday and a flat Metric on Sunday. Easter Hill Country Bicycle tour next weekend and the the MS here I come.