My 1979 C-161 has the Sundstrand pump 90-1173 transaxle. The transaxle needs work. the Sundstrand pump works but I wonder what shape its really in as the tractor appears to have had a lot of use. since the Eaton 1100 is the better hydro, what would be required to do a complete pump & transaxle swap from a Sundstrand to a Eaton 1100. Has anyone actually done a Sundstrand to Eaton swap?