Memory is so often flawed anyway. We are always literally recalling the last time we recalled somethinmg, notr accessing a sacrosant, pristine, "original" memory. It is like a solitary game of telephone. So even if Conn was not the late 160's that many claim he was, he was much smaller than HW Spinks. Who grew to a lean 212 against Tyson.
The listings here vary, but almost all of them say that you have it a little too heavy for each of them: [url]https://www.google.com/search?q=ali+vs+liston+tale+of+the+tape&client=firefox-b-1-d&sxsrf=ALeKk02EHrsN5rwn_ZPBDhWhfHts7UECOQ:1585621745257&tbm=isch&source=iu&ictx=1&fir=QvZrrdNvhxl8LM%253A%252CnwUa0nc_Sou5YM%252C_&vet=1&usg=AI4_-kQTiUBlSxpjV-lYj9iMphmqhTth1w&sa=X&ved=2ahUKEwiy6_6m1cPoAhUFlXIEHY1-A9sQ9QEwAHoECAEQEA#imgrc=-_TryojD5Mh9NM[/url]
Conn v. some of the '85 cruiserweights probably would have been more competitive. Conn v. a young Leslie Stewart or an old Marvin Johnson could have been great fights too. Matching him up against a much bigger man who's also his match in skill, mobility, smarts, and toughness just doesn't seem fair.
Billy Conn that fought Joe Louis 1st fight would be a very tough fight for Holmes. I think any version of Mike Spinks would be a troublesome fight for Holmes.and I consider Billy Conn up there Holmes had a great jab but was open to right hands and Billy had good hands. The combo power of the great Joe Louis was enough to take Billy out 6 punch combo I think Billy had the speed and movement to make this a close fight