If you cut the strips 3" ( finishing at 2 1/2" )
and add the first border cut at 3" ( finishing at 2 1/2" )
Add 2 more rows of blocks to the top and bottom only, to start making it a rectangle
Th quilts dimensions will be 47 1/2" X 57 1/2"
If you add another border 3" wide (cut at 3 1/2" ) the dimensions are now 53 1/2" X 63 1/2" Which should pretty much cover the top of a full bed. Add more borders if you want it to drape over the sides