I have also used inkjet paper for decals. Dark colors work, light do not work well. Tried yellow lettering for a project, it was a fail. Even tried getting laser printer decal paper and had it printed with a laser printer, fail on that. I have had success with black print on clear decal paper and some colors on white decal paper. The boxcar is black print on clear decal paper, the Alco herald is printed on white decal paper. The MOW truck decals were printed on white decal paper, fortunately the white background blends in to the white paint.
I have used Testors decal bonder overspray on some of these, later ones where just a krylon clear overspray. Both seemed to work well.
