Since it's gutted there won't really be any weight savings to speak of. A thick test pipe might actually weigh a little more. Either way it'll be minuscule.
So if you're just going for a look, consider a dump pipe. I think they cost about the same and you can play with noise or accessorize it with a motorized flapper.
Way back in the 90's when I bought my THDP, I opted for the dump instead of 3" cat which I already had.
If you have a gutted cat, like everyone said theres not much advantage to the dump, except if yah wanna open it and be loud, the turbo DOES sound good tho with it open