Lifter/Cam Question

I have a 1993 Skylark with the 3.3 Liter V-6.

What type of lifter does this engine have,are they the hydrolic flat tappet type or roller?

The reason I am wanting to know is because the new SM oils have lower amounts of zinc which can be hard on certain types of cam/lifters.

Some flat tappet cam/lifters can be harmed by the lack of zinc.

Thanks for any help.