which component should i put the better cable on?

Probably depends on the quality of each component, but assuming all things being somewhat equal, I'd opt for installing the pc on the amp.

Only because that is the component in which I've noticed the greater improvements from every electrical tweak I've made.

-IMO

Phil - Use your ears. Who cares what the justification might be as regards to the pcs cost. Listen for a few days (assuming that they both have plenty of hours on them) with them in one configuration (pre-1k and amp-250), and then switch (pre-250 and amp-1k) for a few days. The configuration that you find most pleasing wins. Enjoy.

The price in this issue plays not a large role whatsoever.
First you need to know what manufacturer suggests or how the powercord was built(I think for $1k you should!).
For poweramps usually high-gauge shielded powercords are better to filter large fluctuation currents that greatly affect high-gain amplification stages. Shielding adds an extra capacitance and inductance but for high currents flowing they only slightly deviate the overall impedance.

For small signal components you need as newtral as possible so that you have in ideal case the resistive impedance.

Ultimately you have to decide where it sounds better, but my two cents would be to put the best cord on the source. Componants down stream will never add what was missing at the start.
Another issue might be the application for which the cord was designed. I have "front end" cords and "amp" cords that are designed to work best in thier certain application.
Give 'em a listen!

I have found that power cords on the source make the biggest sonic impact on a system. Also the IC from the source to the preamp.

So I would start there and try out other options along the way (moving the cords down the signal chain).

KF