what would you guys recommend using to cut down a redline flight Spindle Sleeve a lil over a 1/8 of an inch??
do you "really" need it in there?

Man you don't need much. Just enough to ensure the bearing is making solid contact with the sleeve as opposed to the cup hitting the edge of the bottom bracket edge. I measure it to flush and then add just a tiny bit. I hate the look of the cup sticking out too far. Maybe leave 1/32 and see how it looks. 1/8 seems like a lot of gap to me.

first, i'll tape off where the cut needs to be to make sure i have a straight line. next - if it's more than a few mm i'm cutting off - i'll hacksaw it just short of the tape. then (or if it's only 1-2mm to begin with) i grind the small remaining bit down flush to the tape.

like cutting anything, it's better to cut it too little and have to go back and cut more than to cut it too much the first time.

i usually cut (or space) mine so a cup is out of the frame 1mm, or so.

Tha tape idea is absolutely right. I do the same thing Coaster. Typically I file the spacer down on a flat file (on a table) and keep an eye on the tape line. If you have to file a lot, cut it first of course like you said, but filing always helps me get a perfect line. 1 mm sounds right too. See, I'm just piggy backing on your good input.

thanks for the advice guys.. i may just try the tape and file method.
i'm sure it'll be a good workout! lol

I believe you can get shorter sleeves and then just add crank arm washers to make up the difference. My biggest concern with cutting one down would be ensuring that the edge of the sleeve is parallel with the other end so that you don't have angular loading on the bearing. I've had a few bottom brackets go in slightly off-parallel due to thick paint on the BB shell or whatever and the result is a bottom bracket that does not spin well at all...