I would recommend that you first talk to the shop who installed the SC to see if they can offer some assitance in lowering their price per hour. With this information you can then plan your talks with Alpine. State who you are and the VX forum. Members here are interested in the upgrade but I am sure that their decision will ride on the customer support. Be kind and be prepared and willing to negotiate. Will they pay 100%? Expect not.
If the shop offers you a discount rate then you now have a baseline to start negotiating with Alpine. Don't tell them the new discount rate just negotiate either a labor per hour fee or a total cost fee. Hopefully they will bite for the hour fee and if you get your negotiated Lower price fee then you basically got Alpine to pay for all the fees to redo the work.
Last option is that it might be cheaper to fly a VX member to PHX than to pay for those Labor costs.
Before talking to Alpine I would also contact TONE. He might be able to help your situation and since he deals with them he might inform you what Alpine's response might be.
I hope it works out. BTW I asked you before which shop you went to. Maybe I missed the response but could you reply again?
For the rest of the members thinking about SC I would recommend going through TONE even if it is more $$. Call it a peace of mind but I doubt Alpine would have had a problem with TONE calling.
Best of luck,
P.S. Just noticed TONE's B-day today. Happy B-DAY!