Hi Colin.
Yes, it is. (Actually, you may even not to delete it, but to rename to something else. ('Update_1' in my case))
Also, on my system Chrome installed itself not into Program Files, but into Users\\AppData\Local\Google, but I am sure this is irrelevant.
P.S. BTW...
I seem to remember, that the Chrome\Application folder (mentioned by Colin) contained several subfolders with the names corresponding to the all Chrome versions installed previously. Each folder contains the Installer subfolder with Setup.exe.
I never tried this, but maybe it is possible to copy the entire <version> folder to some other place, uninstall Chrome and try to install from the saved folder?
Will appreciate if someone tris this and let us know the result...