i need help w/duster engine

first page 2nd post.
I said
we havent picked one out yet..
the old one is

Purple Shaft Cam & Lifter Kit
Adv. Duration: .292°/292°
Dur. @ .050'': 248°/248°
Lift: .509''/.509''
Centerline: 108°
Basic RPM: 2600-6000 RPM
Bolt Pattern: 1-Bolt

i have Doug Herbert roller lifters..was shopping his site..
but ...i dont know exactly what to get...
i really want to put a roller cam in it...
mel.

Mel.