New Moss Carb Float Bowl Bolt

After trying everything to stop gas from leaking from the union between the  
float bowl arm and the bottom of the H6 carb on my '60 TR3A, I'm about to  
install the alternative bolt, cup washer and new rubber seals from Moss.   Does 
anyone know if this will necessitate a change to the float setting?   Anyone 
installed one of these with good results?  Any tips on making it  work?
 
We just can't have gas leaking over the exhaust pipe.  Lucky so  far...
 
Thanks, all.
 
Bill Stagg
1960 TR3A