Tim,
I installed a GM throttle body EFI on my 51 and on my 86 and have headers on both of them, I only installed one also and put the O2 sensor on the header collector, worked out sweet and Ive had no problems what so ever
Check it out http://rides.webshots.com/photo/2078676030100410726AVAMhJ
Good luck bud

Todd

Some people are like Slinkies, Their not really good for nothing... But they still bring a smile to your face when you push them down the stairs.

1951 3100 350 TBI Gallery Toddzilla... "$old"