When Spiderman was hurting Hulk, he didn't just use his fists: He used objects in his environment to beat Hulk down to the point where he was screaming in agony.
I didn't say he used his fists. My post was to demonstrate that Spiderman is clearly not as strong as the Thing.
I do question a Hulk who can be beaten down by someone pummeling him with things like I-beams since that's the sort of thing he normally shrugs off effortlessly, but I won't argue that here.
If Spidey is going to have a chance against Ben, he has to do stuff like you're describing. He has to knock him off of buildings and hit him with girders and drop cars on him. If he does that (depending on what's available in the environment) he can win, though it's not a sure thing.
In a straight up fistfight without using environmental weapons, Spidey's chances are close to 0.
As for the comments that webbing could finish the fight easily. You do get that sort of thing in dialogue a lot, but when has it ever worked against a powerful foe? Here's a short list of people who have broken free who are weaker than the Thing: Doc Ock, Lizard, Man Mountain Marko, and Wolverine. (I couldn't find the scan but in Marvel Team Up 117, Spidey webs Logan's arms making it impossible for him to use his claws. No big deal, he just tears free with no apparant effort.)
Webbing is a useful tool, but it's strength is portrayed even more inconsistently than Spiderman's, and it's never guaranteed an automatic win over any super-powered foe.