Paint on fender wells and firewall

[dakotakid]

I have a '69 Berger Camaro with a fairly decent restoration. One problem though...when the restoration was done, the fender wells and firewall were painted gloss black. Rather than take everything apart and redo it all, is there a way with some type of compound or mild chemical to "flatten" the paint somewhat (without removing it), so that it has a semi-gloss satin appearance? Thanks.