Before tackling the forend tip and barrel band it is important to get the action itself bedded first. This means that the bottom of the action is in full contact with the corresponding surface of the stock and that the rear face of the recoil lug is in full contact with the corresponding surface in the stock. Most folks don't have inletting black, so you can use a thin layer of wife/GFs red lipstick if she is agreeable.
On a new stock the time to test the barrel for pressure against the barrel channel in the forend tip is after the action has been bedded correctly. If the pressure is excessive (more than 5-7 lbs) to lift the barrel out of contact with the channel in the forend tip, then you can relieve the barrel channel incrementally with some sandpaper on a piece of 5/8 inch dia dowelling until the pressure is right. The armorer's manual for the M1903 stipulates that there must be contact between the bottom of the barrel and the barrel channel and that 5-7 lbs pressure is required to lift the barrel out of contact with the barrel channel. It does not call for a barrel to be floating out of contact with the forend at this point. In my experience an M1903 can shoot very well with a fully floating barrel (no barrel/stock contact), but that isn't the MILSPEC solution. I suspect that one of the objectives in stipulating upward stock pressure at the forend was to stabilize the stock and prevent warpage/distortion under service conditions.
Having done that, you can then deal with the upper band. The band itself should be a push tight fit to seat it on the front tenon of the stock or maybe a tap or 2 with a wooden block to fully seat the band.
Once the band is seated you can check for contact between the metal of the band and the top/upper surface of the barrel. If there is contact between the top surface of the barrel and the metal of the band (check with a shim of some sort to verify clearance here) and the amount of barrel pressure at the forend tip is right, then you can grind some metal off the band where it binds on the barrel to get some clearance.
The upper band screw serves only to prevent the band from coming off the stock. It does nothing to locate the position of the barrel upwards or downwards in the barrel channel at the forend. Do the following to drill the hole for the upper band screw;
1. With the barreled action removed and the upper band fully seated, drill a 1/8 " hole half-way thru the forend tip from the LEFT side as you look down the stock from the rear.
2. Next, drill a 1/16" hole from the RIGHT side to intersect with the 1/8" hole.
3. Next, remove the upper band, select a drill bit just slightly thicker than the upper band screw and drill all the way thru from the LEFT side.
Maybe I'm telling you how to suck eggs, but you need to mark a pilot hole for the drill bit on either side with the upper band in place. A slower drill speed is good and a drill press would be useful, but not essential to drill the hole at the right angle.
The end state to all of this is to have the forend set up so that you can put your thumb on the top of the upper band and using the same hand, lift the barrel out of contact with the stock channel at the forend tip using 5-7 lbs upward pressure (you can verify with a trigger pull gauge or spring balance). There should be enough clearance between the top of the barrel and the upper band to allow you to pull the barrel up out of contact with the wood. I just went thru this whole nut roll again last week to install a new GI stock on a M1903 that I built from parts using a new GI barrel and everything worked out ticketty-boo. It really isn't that hard, but you need to work at it slowly to get everything right.
