718D Help Engine Swap

I have a 1989 718D with the Kubota D600 engine that finally hit its end. Everything else on the mower is fine. I have a buddy with a D902 that came out of a Toro Z-Master. I was wondering if anyone knew if these would switch out ok or if the configuration is just too far off. Thank you in advance

This may be too late to help you but go to www.kubotapartsdealer.com/how-to-find-engine-model/ The engine codes are broken down including oem specs, etc. Grasshopper has its own code: MRG Don't know if its different than the engine you have available.