Spark plug gapping and size windsor jr head

I am not sure what part number you need for autolite, the instructions recommend an Accel 276 which is one heat range colder than stock. I asked NGK and they said to use a UR5, also one heat range colder than stock. So if you are set on autolite, find out which number is one heat range colder than stock. That is the only difference from the stock one, and the gap is .044

I think an autolite 24 or 25 should do, I think I gapped mine at .050.

Matt