Unfortunately, last I checked you, cannot have Chrome 32 and 64-bit versions installed on Windows at the same time. So as a workaround you can install one production release (stable) and one Canary development release.
Chrome Release Channels page notes that canary “… will run in parallel to any other Chrome channel you have installed, it will not use the same profile”
Downloads
| Production 32-bit | https://www.google.com/chrome/browser/desktop/index.html |
| Production 64-bit | https://www.google.com/chrome/browser/desktop/index.html?platform=win64 |
| Canary 32-bit | https://www.google.com/chrome/browser/canary.html?platform=win |
| Canary 64-bit | https://www.google.com/chrome/browser/canary.html?platform=win64 |
This guy installs the 32-bit production release and the 64-bit Canary