Can you swap 1 1/8 inch forks for 1inch forks?

The simple solution shall be:

• for the lower end of the headtube, I keep the integrated bearing and fork race. To bridge the gap between the (1 1/8) fork race and the 1" forks, I would make a simple small ring on the lathe.
  
  

Don't know the forks you are planning to use .. but the 1 1/8 fork race may be larger then the crown on the fork so the race will simply move vertically pushing the forks up into the head tube if it is not sitting on the crown on the fork. Solution would be to make a complete new race ..

Asthetically .. I reserve judgement until seeing this as in my mind I think the transition top and bottom of the headtube could be challenging ?