There is a very large number of wires that will need to be lengthened. Moving the box up to the speaker location might be do-able, but the dash will definitely have to come out minimum. In today's world, I would hate to see how much that will cost. Finding someone competent enough to do the job would be the next nightmare. I'm thinking a street rod shop that does vehicle rewiring on a fairly regular occurrence would be your best bet.

I think you need to make friends with a repair shop near your home, so you will have someone close to you that you can trust to do the things you can no longer do. I suspect that list of "can't do anymore" will grow longer as you get older. Much as it sucks, that is how life works, might as well get used to it. At least you have an excuse, you didn't just grow old and turn into a feeble old man, like I am. Gene