Found a couple minutes this morning when wife wasn't looking to disappear into the basement. I've decided to use the factory "TV" to mount my LED's. After a bit of turning parts this way and that, and contemplating, here's my started assembly.
Standard 3/4" by 1/8" aluminum bar available at most home improvement warehouses for cheap, grommets from a packet of 8 or so at Autozone, also fairly cheap.
Carefully drilled and marked holes to get heatsink to line up nicely.
That's about as far as I'll be able to get today. Afternoon is booked up. Yes, the red lid fits over neatly with zero modification. I had to Dremel the shield just a little to get my bar to clear. I ordered empty bayonet sockets from superbrightleds.com to wire to my LED's so that if for some reason this whole project is an epic fail, I can just pop the normal bulb back in and go for a ride.