Not sure what your problem is John. But here goes on what I have found successful.
First the paint needs to be as flat and smooth as possible and to receive a coat of a varnish of some sort in gloss. This is in order, hopefully, that every part of the underside of the decal will touch the varnished surface. any part which does not will allow light thro to the varnished surface which will reflect back causing what is described as "silvering".
This is my decaling way. Cut off as much of the permiter which causes the silvering. That is the clear plastic border.
Place paper up and spray water on the paper just enough to release the decal from the paper. The idea is to wet and soften the backing not the decal.
Wet the varnished surface a little. Place the decal and backing virtually in place onto the varnish flat just a little to one side of the final position ie a little off set.Then carefully slide the decal just that distance you have offset onto the varnish. Gently hold the decal in place and gently pull the backing away. with luck you should then be positioned correctly. If not a large soft brush with water gently edge the decal that last move into position. Brush any water gently form under the decal (this should be minimal unless it is over soaked).
Used this method for about 3 years and had good results (except last model the Gladiator and nothing would save those rubbish decals).
I have used Micros before the above method and just found them more of a problem than a help as they disintegrate the decal. I use them now only when I have a problem with the above. Water will not wreck your decal. Poor positioning and lots of moving them around will.
Lots of members may not agree with my method. But all the decal on this Wessex were placed just with the method above. This includes the black decal with the blue lines which wizzed around in every dimension possible. Micros were used only on one stubborn roundel. All the decals sank into the panel lines which on this model were quite large. Most times the panel lines are half the size. There was no silvering except for the one decal which eventually settled down with a Micro coated a number of times..
Laurie
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