A few months ago, I was at a gun show and purchased my first AR15 - a BM Dissy.  I wish I had waited until after I found arfcom, but man... I got all weak in the knees and just couldn't help myself.  

I know the longer sight radius is better, but I just don't like the way it looks as much.  I purchased an m4 car upper off the ee yesterday, so I was wondering what to do with my Dissy upper.

I thought about selling it on the ee, but i probably wouldn't get that much for it.  So, I thought about modifying it for another rifle for my buddy.  Since it uses the car length gas system, can I just take off/move the FSB and put car/middy length hand guards on it?

Would there be any other advantages/disadvantages to modifying this?

Thanks for the input.

As soon as I find out how, I'll add a picture or two.

convert your dissy upper into a sniper /varmint rig.

here's my dissy

colt model 605A clone

Quoted: <snip> I thought about selling it on the ee, but i probably wouldn't get that much for it.  So, I thought about modifying it for another rifle for my buddy.  Since it uses the car length gas system, can I just take off/move the FSB and put car/middy length hand guards on it? Would there be any other advantages/disadvantages to modifying this? <snip>

Yup.  You can cut that FSB right off.  Course, you do still have the taper pin holes in the barrel where the FSB was.  Doesn't effect performance any, but may be aesthetically unpleasing.  As an alternative, you could post on the EE for a straight-up trade for a carbine or rifle upper more to your choosing.