Well, Excluding a few from the late 90's and the last decade, I have (Going by by records it this point)
-1981 93508
-1980 92908
-1977 92502
-1989 100708
-1975 100902
-1985 92908
there is also one more, i havent noted its model yet, but i can remeber it, it's a 197s Rover Pedigree with the original 148cc Briggs on it.
I will look for the Minion when i get a chance, and as i go through restoring the above engines, i will document the restorations in a thread. (Looking forward to the 75' 100902, thats the Rover Super Four 21, From Redeye)