English to Spanish Bus/Financial Manufacturing Packaging/paper products

From an Employee Resource Manual for a US business, under the section on vacation scheduling and pay. Target language is US Spanish, manual geared for an 8th grade reading level. I've chosen to use the informal tú in the manual because of the friendly, congenial atmosphere the management wants to try to promote.

The full sentence is "Pay in lieu of taking vacation must receive prior management approval and it will not be counted as time worked when computing weekly overtime."

Having no idea of whether there's some formulaic way of saying this phrase, here's my attempt:

Si quieres que te paguen por la vacación sin tomarla, tienes que conseguir autorización previa de la gerencia, y las horas de vacación pagadas no contarán como horas trabajadas cuando se calculan las horas extras por la semana.