Prevailing Wage Fringe Posted to Jobs

Does anyone know of a way or even a report that can get the prevailing wage fringes posted to the cost of the job without processing payroll first?  We are normally only on a job site for 1-2 days.  If it is a prevailing wage project, we currently have to wait until payroll is processed the next week in order to run job cost reports and invoice the job, because of fringes not being posted before payroll is processed.  Thus causing an influx of billings in one day.  I do not do payroll, so I am not sure of the entire reasoning other than being told they can not get fringes to the job before payroll is procssed or it creates a nightmare to correct problems if there are any.  Even if there was a report or way to roughly figure fringes on a job in order to speed up the billing process it would help.  An Office Connector Report?  Any suggestions or thoughts on this would be extremely appreciated.  Thank you!