Well I'm glad you took the plunge, it's agreat looking custom. Remember when you shorten a barrel you'll need a front sight with overall height from the bore centerline a lttle higher than the original.
Personally I like to make my customs look like they could have come from the factory. Therefor I would cut off the original front ramp sight, remove material from the bottom of the factory ramp but leave enough so it's higher than originally. Screw it to the top of the frame with a flush headed, countersunk screw hidden in the dovetail under the front blade. If after you test fire the gun, it's too high you can shave off the bottom of the ramp by just unscrewing it and replace it. When you get the height right, put a drop of locktite on the screw.