Simplify a large nesting string to use in Excel 2003

[Keven89]

How do I simplify the below string to use in Excel 2003. It works in Excel
2007. Is there an easier way to get the same result? Perhaps vlookup and how
would I set it up?
I appreciate any help.
Signed,
Rookie Excel dude

=IF(AND(($C$15)<=270,($C$14)<=20),"vct4482b",IF(AND(($C$15)<=270,($C$14)<=30),"vct4493b",IF(AND(($C$15)<=330,($C$14)<=20),"vct4466b",IF(AND(($C$15)<=330,($C$14)<=30),"vct4478b",IF(AND(($C$15)=330,($C$14)<=40),"vct4476b",IF(AND(($C$15)<=400,($C$14)<=40),"vct4477b",IF(AND(($C$15)<=400,($C$14)<=50),"vct4473b",IF(AND(($C$15)<=450,($C$14)<=60),"vct4467b",IF(AND(($C$15)<=450,($C$14)<=70),"vct4479b",IF(AND(($C$15)<=550,($C$14)<=80),"vct4471b",IF(AND(($C$15)<=550,($C$14)<=90),"vct4469b",IF(AND(($C$15)<=570,($C$14)<=100),"vct4468b",IF(AND(($C$15)=630,($C$14)<=110),"vct4484b",IF(AND(($C$15)=750,($C$14)<=120),"vct4472b",IF(AND(($C$15)<=750,($C$14)<=130),"vct4470b","NA")))))))))))))))

 

[Shane Devenshire]

Hi,

Something of the form

=IF(AND($C$15<=270,$C$14<=20),"vct4482b",IF(AND($C$15<=270,$C$14<=30),"vct4493b","")&IF(AND($C$15<=330,$C$14<=20),"vct4466b",IF(AND($C$15<=330,$C$14<=30),"vct4478b",IF(AND($C$15=330,$C$14<=40),"vct4476b","")&IF(AND($C$15<=400,$C$14<=40),"vct4477b",IF(AND($C$15<=400,$C$14<=50),"vct4473b","")&IF(AND($C$15<=450,$C$14<=60),"vct4467b",IF(AND($C$15<=450,$C$14<=70),"vct4479b","")&IF(AND($C$15<=550,$C$14<=80),"vct4471b",IF(AND($C$15<=550,$C$14<=90),"vct4469b","")&IF(AND($C$15<=570,$C$14<=100),"vct4468b","")&IF(AND($C$15=630,$C$14<=110),"vct4484b","")&IF(AND($C$15=750,$C$14<=120),"vct4472b",IF(AND($C$15<=750,$C$14<=130),"vct4470b","NA")

I removed a lot of unnecessary parentheses, those around things like ($C$14).