Massey is owned by AGCO and one big reason "some" of the Masseys had front dif locks is, because the tractors were built by SLH, (a VERY GOOD Italian tractor mfg.) and painted Massey red. Lot's of the SLH tractors have F.Dif lock, one of my tractors has it too...
Anyway, Landini built a TON of orchard tractors in other colors and sold them in that color mfg.'s name, what made me not care for the Perkins so much is, LOT's of them had bad cams that had to be replaced and many of them have small oil leaks... Of course, Perkins has been owned by CAT for several years now, so maybe all of those things have been addressed by now?
SR