Price adjustment - plsql call

Hello,
I'm trying to get from QP_PREQ_PUB.PRICE_REQUEST
the same adjusted value I have on an order line (it works on ONT form)
Let's say, I want to simulate the pricing engine behavior
I have the qualifiers values to pass to the engine.
my goal is the engine can tell the right modifier line and apply the % operand to the list price (modifiers passed are the ones I expect to match the right line).
I'm not passing the manual adjustment %. I want the engine to return it,
I can easily get the item list price but cannot see the expected adjustment amount