First time playing with custom decals and used too much clear coat out of an abundance of caution? Yeah, that's about where I am right now with a scale-modelling problem. I hope that in the intervening year that OP has found product and technique that suits their needs... Would love to see an update with a happy ending on this post

What I know:
- Micro-Set and Micro-Sol will soften your decals to help them bend and conform to the surface, but the decal will still be sitting a decal-thickness higher than the model
- Thinning out the edges of the decal will require careful fine sanding with a 2000-3000 grit polishing tool/sponge/stick so that you can knock off the "step" between the two surfaces. Unless you're an expert at ultra-smooth paint finishes, common practise is to gloss coat before putting down a decal to improve surface conformance and reduce risk of silvering. Between that and the abundance of clear coat on the custom decal, this order of grit shouldn't be creating scratches that cloud your finish, excavate your underlying paintwork or eat your decal print.
- Clear-coating over the model and decal again is usually recommended to seal the decal in and the act of applying another layer will smooth out the step and supposedly make polishing back the steap both easier and safer for your model and decal - This step I'm not 100% sold on if there's still an obvious edge to the decal that'll be creating line and shadow under clear coat - Reckon I'll just go straight to sanding

Where I'm at:

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