Warrior and banshee spindles cannot be easily modified for use on a blaster. Drilling the upper ball joint mounts does not leave much material at all because the banshee and warrior spindles use taper bolt upper ball joint mounts.
Luckily, yamaha had enough sense to make the 03+ blasters with hydraulic brakes with the same suspension as the older models. 03+ spindles will bolt onto the older suspension and the banshee or 90+ warrior hubs will fit on them. If you find it prohibitively expensive to source factory 03+ spindles, there is a member who modifies older spindles to use hydraulic brakes. Norman420 does an absolutely outstanding job and his spindles are professional units which only differ visually from the factory yamaha units. He does a LOT of work and has a VERY reasonable price on them.
Once you have norman420 or factory yamaha spindles, 90+ warrior or any year banshee hubs will slide onto them and pretty much any nissin caliper will bolt on. Honda 300ex and 400ex 05 and up foreman and rancher, yamaha banshee, warrior, big bear, kodiak, YFZ450, suzuki LTZ400, kawasaki prairie, mojave, or kfx.