Signatures of acid rain at KT boundary I read in Walter Alvarez' book T. Rex and the Crater of Doom
that the Earth's collision with the large meteor leading to the K-T extinction catalyzed the reaction of atmospheric oxygen and nitrogen molecules to form nitric oxide, which in turn formed highly corrosive nitric acid when combined with water. In addition the impact is thought to have volatilized huge amounts of sulfur contained in anhydrite, which in turn formed sulfuric acid.

This question refers to a thickness of  $\pu{1.8m}$ for the section where iridium could be detected in the K-T boundary, suggesting that the resolution may be too low to note the effects of acid rain following the collision. 

Is there evidence in the geological record of the formation of these acid species thought to be associated with the collision, say from deposits and/or effects of the ensuing acid rain?
Estimated sulfur release 325 gigatonnes = 325,000 teragrams. The numbers in this diagram are in teragrams

Sulfur Cycle

so the release is $\approx 1000\times $ today's annual sulfur cycle.

I think most of the sulfur compounds would be washed into the ocean and then deposited into sediments. I can't find how much sulfur is currently in the oceans, this article says gigatons (because you can smell it). I also can't find how fast the increased sulfur would be deposited.

Another issue is that, unlike iridium, there is normally a lot of sulfur in marine deposits, so it is hard to distinguish what comes from Chicxulub.