To see regimental assignments, follow the link provided earlier, using the volume and page to locate the citation. I'll go ahead and do that here --
http://digital.library.cornell.edu/cgi/t/text/pageviewer-idx?c=moawar;cc=moawar;q1=Wheeler;rgn=full%20text;idno=waro0099;didno=waro0099;view=image;seq=1073

You may need to copy and paste the entire URL in your address line to see the page. The remainder of Wheeler's command will appear on the page which follows. Please reply if you have other questions.