Blitz is right, there are plently of firms about that can carry out frame alignment checks. They will need the engine, forks and wheels fitted to do it.
Over here they call the rig a "Motoliner" probably the same bit of kit as your EZliner. It costs about £50.00 (sterling) to get the check done over here, the expensive bit is if it needs straightening.
Have you ridden it since it was damaged?
You can check the frame welds to see if they have split, or if the paint has cracked or flaked off. They are usually a good indication of damage.
Hope this helps