What was the problem with soldering the reducer?
for me it was very difficult to push that 3/8" copper through the reducer it was a very very very tight fit and once its all assembled with the hose to deal with it was a PITA. if i were to make another one i'd
roll the hose and copper out straight
slide the reduce on the 3/8" copper first then solder it all up
then wrap around the corny keg for a perfect circle
doing those two things makes this no harder than making a IC chiller
-=Jason=-