An article I found written by the legend himself, in the San Francisco Call. Link: https://chroniclingamerica.loc.gov/lccn/sn85066387/1905-07-09/ed-1/seq-10/ PDF, if you want to download: https://chroniclingamerica.loc.gov/...la_ver01/data/00100480669/1905070901/0169.pdf
The weights aren't known, Gardner and Fitz both stepped on scales fully dressed and were light enough not to move it set to 168Ibs. So they weighed less than 168 fully dressed, but beyond that is just people guesstimating as far as I know. He also weighed 164Ibs fully dressed before the Ruhlin fight.