Looks to be plastic from the way it cooled. Not rubber.
Did it harden, or is it still flexable?
Yes it is plastic.Not very pliable (now),and look like it was a brownish yellow but hard to say.You can clearly see where 2 1/2 inch bolts went through it.Was there a plastic piece between where the steering shaft connects to the gear box?
Going to dealer today to play with a srt-8 challenger so I will show it to the parts manager.