All 216 engines had mechanical/solid lifters.
All 235 engines through 1949 had mechanical lifters.
From 1950-1955 235 engines used in cars with Powerglide transmissions had hydraulic lifters (except in Corvettes).
All car 235 engines from 1956 onwards had hydraulic lifters.
All truck 235 engines had mechanical lifters.
All USA 261 engines had mechanical lifters (these were only used in trucks in the USA).
All Canadian truck 261 engines had mechanical lifters.
The Pontiac car 261 engine was only available in Canada and it had hydraulic lifters.
One unknown:
It is not clear if USA trucks with Powerglide transmission and 235 engines had mechanical or hydraulic lifters (1950/60 and later).
All 1958 and later 235 blocks and 261 blocks were drilled to allow the use of hydraulic lifters.
