should i use a wire harness ??

the girlfriend wrecked the HONDA, so i gotta install it into the new VOLVO. (1995 850 turbo).

i need some advice here with the new install...

regarding the HEADUNIT, (Alpine CDA-7995), should i buy a wiring harness so i can tap into the important/necessary stock lines, i.e. ANTENNA, SWITCH, ILLUM & maybe Constant 12V & Ground? or should a tap-in higher up, above the harness? Keeping the cars Re-Sale value UP is a definite concern of mine, (thats why im thinking harness).Does this sound like a good idea? are there any implications?

Should i use the stock CONSTANT 12V & GROUND? or run my own? (which i'd like to avoid, because my dist. block is in the trunk & id rahter not run power BACK up to the front). The Alpine H/U is pre-amp only, so maybe the vehicle power is suficient?

Thanks in advance for the help! (my last install was super-sweet thanks to everyone out there, & i cant wait to get it into the new ride!)

I would use the harness. Tie all the wires from your HU to the new harness and then plug into the factory harness.  Simple as that .  I wouldnt worry about running your own 12 volt wire and ground wire unless the unit dims badly when it is played at high volume.  If you are not using  the internal amp in this unit you will be fine to use the stock wires.  Brian