Hi Dave,
Welcome here.
For starters the GXV160 has the wrong bolt pattern, can be fitted but it is a lot of work getting the holes in the right place. I did it once and never again. Motors are in short supply at the moment as you will find if you look up vertical shaft motors on ebay. You also have to watch, some of the 160cc motors on ebay are claimed to be Briggs bolt pattern but they aren't and are a pig to fit. Last time I checked most of the 13hp motors were out of stock What you must look for is Briggs bolt pattern which is standard on all motors up to 20hp I believe. Just be wary of the 160cc ones and all the Briggs pattern motors have 1 inch shaft
