After reading your post, when you say chassis, I'm assuming that your damage is to the bulkhead only. I'm dealing with the same problem you are. Check your clutch alignment out thoroughly. That will tell you quit a bit about the extent of the damage. Or at least it did in my case. Even though the damage to my sled didn't look all that bad, I spent several hours trying to get the clutch alignment correct by shimming and slotting the motor mounts but to no avail. Once the bulkhead is bent, your s.o.l.
I think that unless you have some type of jig, or maybe another bulkhead to take measurements off, the ability to do some metal work, and the patients to get your clutch alignment perfect (if it is out of alignment), your best bet is to replace it with a straight one or just ride it if the damage is not effecting performance. Thats just my opinion though. Replacing the bulkhead is a quit an undertaking but if you want to keep the sled I think you would be happier in the long run.