Lowering Max Tire Size

[JaimeC85]

hey guys new to the forum. I have an 85 GMC 1500 and was planning on dropping it 4/5. but wanted to know if the tires i just bought would work with that drop. they are 275/60 r15. the rim is 10 inches wide.

Also is that the lowest possible drop to go on the truck without a cnotch.
thanx in advance. i know it gets posted numerous time.

http://img15.imageshack.us/i/imag0223to.jpg

http://http://img219.imageshack.us/i/imag0224h.jpg/

http://http://img820.imageshack.us/i/imag0225l.jpg/'

some pics of my truck