Well, every dismantled component could give a bonus to further dismantling of the same kind of component (perhaps the exact same). Having the same 2.5% chance per try implies your engineers are constantly bashing the thing with wrenches as opposed to learning more about it with every try, even if they can't quite grasp the whole technology. You'd think they'd know more about an advanced drive when reverse-engineering their 20th specimen, as opposed to the first.
Alternatively, instead of providing an invisible bonus to a chance for complete discovery, every dismantled specimen could provide a fixed (or somewhat variable) number of said technology's* RPs. This way, you could eventually unlock the technology or have the scientists use the engineers' insight to research the tech in question with a headstart (or even with most of the work done, if a lot of RPs have been collected beforehand).
*Or a previous, related technology if the component's so advanced you can't research its immediate tech right away.