Epa Chamo!
When working with Venezuelan Installers, I found useful to set up some space in my garage, bought a router and a couple of other tools and always plan carefully the installation in stages...I end up doing some of the work myself and give them detailed instructions on the rest. To go active without having a tech that is trained in tunning you could seriously mess things up. In my opinion, your two best choices are: 1. pick a kickpanel loction, keep all drivers close and start with the stock crossover (KISS!). 2. If you REALLY want to go active and separate drivers...get a JBL MS8. It's not cheap, but it will do all the time alignment and EQ properly in a pinch. Also, if I remember well, DON'T LEAVE THAT THING PARKED ON THE STREET!...lol..
Also...the SR6500 are designed to work well when mounted coaxially. I Have Coaxial Cabasse Gallia speakers in my HT and, while the tweeter does loose some "air", the concentric mounting creates a beautiful sweetspot with incredible imaging...give up one thing but gain another one... make sure you try them both ways to find out which one you like best.