The only variable in what you're asking is the eventual cost of AWD. As for the rest:
EAP: $5,000 (required for FSD)
So your total so far would be $44,000, I think you'll be safe if estimate $5,000 for AWD (Elon said it would be less than that), so you'd be looking at a total of $49,000, not including taxes. If you reserve in two months and do not configure or take delivery for 12 - 18 months you'll likely miss out on all the federal tax credit, although there would be chance to get the quarter credit of $1,875.