[chris vickery]

Sylvain
The fact that your flathead is a French made post war version for the Simca may also complicate things.
What I understand is that they are a copy of the American 8BA flathead but with superior castings to earlier US made blocks.
They also differ in the fact that the bellhousing is intergral to the block like an early flathead from 32-47 unlike the original US made 48-53 8BA block which had a separate bellhousing to fit the transmission. These are highly sought after engines by the hot rod community.
The French distributor cover is slightly different in the way the distributor mounts into it and is slightly longer where the dizzy goes in as the distributer itself was also a French design and differed slightly from its US counterpart..
I would have to only guess that if the internals are the exact same as a US made 8BA, then the work required to change over the timing cover will be extensive as previously outlined by other postings.
It is likely that at the very least, removal of the engine from the truck will be required.