i have been using PPG products since around 1982. i don't remember when i attended my first training class when i first started using DBU base coat clear coat system.
if you have any PPG questions pm me here or at IMBOC under the same name.
i have a 08 bullitt.



epoxy thinned out used as a sealer is really old tech, i used to use it over 20 years ago. but now just about any PPG 2K sealer would be a better choice because it will be designed as a sealer from the start epoxy wasn't designed as a sealer when it was developed
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omni base coat works pretty good for what it is but DBC base coat would be a better choice. there is a activator, DX57, for it. it will give the base coat a little help cross linking to help it dry and cure faster. it will also help with durability helping the clear coat adhere better to the base coat. it will spray exactly the same as omni base coat and the same spray techniques are the same. just don't spray the last coats on to dry, the clear coat might de-laminate. omni will have the same problems.
there isn't a activator for omni base. as far as color if it can be made in omni they can make it in DBC.

again i am NOT criticizing your choices of products to use. what you have listed will work just fine. i just hate to see you put so much time and money into a project and have problems with it later on.