There are some differences in the 2 units.
The major difference is in the mounts. The -2 has 2 mounting lugs on the back rear sides of the transaxle whereas the -1 has a single lug at the very rear.
Other than that, mounting it to the engine is just a straight swap. You will need to check you clutch free-play after. There may be some difference in the gear ratios. Those are stated on the transaxle data plate. The ratios might affect your speedo/mileage.
HTH
"andriyko"
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