Please help me!! towing capacity

[medually]

Hello to my American counterparts

I am having a very hard time finding out the towing capacity of my 1988 crew cab C3500 dually with 454 auto. The rear end is very heavy duty with 9 leaf springs (and 1 helper spring) and was set up for a fifth wheel. I am getting it licensed here in Western Australia as a LHD vehicle and I need to tow large boats I have been told they are rated up to 6300kg but need to be able to confirm this to licensing authorities.....your help would be greatly appreciated

[Captkaos]

I just sent you and email on this.
10,000lbs with a platform hitch
13,500lbs with a 5th wheel.

[joesgarage71]

 If you need to print off a copy of the sales brochures for proof.
 http://brochures.slosh.com/1988/chevy.html

[medually]

Hey that is great help thanks guys