Trade up scenario that isn't too expensive?

The biggest question mark here is San Diego.  But right now it looks like QB's go #1 and #2.  For this discussion, lets assume SD goes OT.  What would it take to trade up to #4.  The #4 pick is worth 1800 points while the #9 is worth 1350; a difference of 450 points or the 13th pick in the 2nd round. Is Glennon worth that much? Dallas needs a QB, the top QB's will be gone before they pick. Maybe Glennon and a 4th or 5th? I think Dallas can still get a quality player they want at #9 while also taking a chance that Glennon can be their starter. Not a big gamble for them. If the Bucs could pull that off, they get their choice of DE or Ramsey without paying too high of a price.Thoughts.....