Primer

You need some DTM Epoxy for just the metal. Don't spray it over the filler you already have on the car, just the metal. I use Tamco DTM HP5300 gray for this.

Tamco DTM HP5300 Series Primer Kit


Tamco DTM HP5300 Series Primer Kit

Then switch to the 2K urethane to spray over everything. I like using Matrix MP-2KGR Quick Sand 2K Primer Surfacer.

https://www.ebay.com/itm/193756009452?hash=item2d1cc213ec:g:zSUAAOSw8-hftT76&amdata=enc%3AAQAIAAAA4DTV2HRwQfi%2Bd3aMgWLthL1sxdWhLOPPgEE%2B1KHGF1J5MfQVM5v3fz5Ui6e9HRH1Ztsi8Z6sA3FmxCNU8cbrOvsyewLgsInRUYZxhJrx84QfdcWZzfRjg6tGy9%2FYEvCtI%2FWUlmZV1ENvUp57J1t%2BRx%2BxtBcOm5S9lUGrP6J0rPsn5nLYNSDcffQOZxDdSm0GDQ%2Fbouvs%2Bb0MMIiRFSO7lMEDhhkrCV5MLH490W3vSh0lJgxrqTUqMatm6QRp4mq55GydIE0oyrz4Hj6HL1WKB7MLxrY7afFliKdLBAA0DGIt%7Ctkp%3ABk9SR6S3g-2uYg

Tom