I checked for this on another site and came across the following extracts from various threads that might be helpful...
"get a typical tange or tioga oldschool headset (if you don't already have that) and get a newschool "Tank" headset.
use the oldschool cups and use everything else from the Tank."
"I did this a few years ago when the ahead setup first came out. I used the cheap Ahead headset with the black steel cups. The only thing you will need to use differently with a 1 inch headtube frame is a set of 1 inch bearing cups. You should be able to use almost any headset that is offered in both 1 inch and 1 1/8. "
"yes, but make sure you get the right "A-headset". not all makes and models will work for this modification. i did it once- i think i used dia-comp tank guts with old tange 1" cups. "
