Custom invoice format in excel

I have client(s) who want invoices in an excel format they prescribe (irritating as this is). Is there any way I can get Manager to generate such an invoice (it has all the information in the existing invoice format)? It is helpful to generate invoices from Manager rather than cut-and-paste etc. Is this a matter of trapping the html code that generates the invoice and converting it to excel?

have you tried to select and copy the content of invoce from view screen than paste to excel ?
it keep all formats and table you only need to disable wrap text and fix column width

Thanks a good suggestion. However, these clients have specific templates in excel to be completed with fields and labels in particular places.

Does he want the final output in his format indipendently from being in excel? In this case you can create a custom theme.

Otherwise you can export the invoices through batch update and create an excel invoice through excel formulas.