crossover frequencies

Hi everyone,
I was just wondering, for all those with amps, what you guys set your crossover frequencies at?
First of all, here's my setup:
Panasonic CQ-DFX572U 50W x 4 max.
Alpine SPR-176A 6.5" components on Clarion APX 201.2 200W 2-channel amp.
Stock rear speakers for fill.
Alpine Type S 12" DVC sub in sealed box on Clarion APX 401.2 400W 2-channel amp bridged.

For the sub amp, I've got the gain and bass boost set OK. I've got the low-pass filter set at around 65-70 Hz. The HU's sub pre-out has a built-in LPF set at 80Hz so setting the amp any higher won't make a difference, right?

I'm just not too sure what to do with the amp for the front speakers. The components came with crossovers but I'm not sure if I need to set a high-pass filter on the amp. Should I? It's currently off so the full range is being sent to the front components (or should I say the crossover). These Type R's can take 50W RMS but only have a sensitivity rating of 86 dB so running them off deck power would probably be a total waste. The crossovers have a variable attenuation level of 0, -3, and -6dB but I don't know what it does nor do I know what it's set at.

My installer did a pretty clean install (i.e. no alternator whine, ground wire as thick as power wire, inline fuse right next to positive terminal, etc) but I still think I can tweak the sound quality a bit more. What should i look for?

links:
My Head Unit
My Front Components
My Cheap Sub
My Cheap Amps

I wouls set the a high pass crossover on the cklarion amp to 80Hz high pass. Yes satalite speakers always need a high pass crossover for the best performance. The crossover the speaker comes with only sets the low pass filter for the mis and the high pass filter for the tweeter.

The 0,-3,-6 is the tweeter attinuation. Basicly thats the level the tweeter will play in relation to the mid driver.

You can use the head units crossover to play with to see where you like them best but I would set them permanently on amps when you find where you like them.