A first-gen Miata and a new air conditioner for my '98 Century. (Yes, I know, but it's a good car for Michigan winters, and it's an entirely competent highway cruiser for road trips.) Maybe a CRX Si VTEC, too.
And then spend the rest of the money on building my own car, with semi-Morgan looks and fully modern underpinnings and the line-six lump from the 1M.
I think I would spend some money on a well built '66 AC Cobra replica with the 427FE side-oiler (yea, I know, the extra front end weight reduces handling).