well I haven't marched with them obviously but I've covered them enough. They're VERY VERY interested in things not turning violent. They're even more interested in making the other side the one that starts the violence if it has to happen. There's a new strategy with these guys, and with the various KKK branches out there. "Let's try to be reasonable racists. We're just here to express our opinion," etc etc etc.
The good news is that unless anti-racist groups start trouble, there generally isn't any trouble at a NSM/KKK rally. The bad news is that some idiot might actually believe them when they say they're reasonable racists.
As to your event, I monitor the various white power idiot boards so I can keep tabs on our local racists. It doesn't look like the idiots at Stormfront, which is one of the larger racist groups, even know about this rally, so it should be relatively small. To give you an idea, the last huge rally I covered was advertised all over everywhere, including Stormfront, and 7 marchers showed up
Funny they should march on the university - - seems they're pissed off at the journalism school because gee, seems there aren't any white supremacist journalists graduating from that particular institution, and what a travesty to the Fourth Estate that is
The location could actually spark your trouble, because college kids just LOVE antagonizing racists.
I would definitely NOT post that sign. Frankly were I you I'd just close the shop for the 5 hours the march is going on - especially if you're within a 10 block radius of campus. You probably won't sell much, and posting a sign like that might antagonize an idiot.