There's not too many decals to add, but some of them are two layers put on top of each other, which is a little bit of a pain.
I recently discovered that Vallejo have produced some decal solutions. They've been around for a while bujt I've only just discovered them. The area which gets the decal is coated with the Decal Fix and is left to dry. Then the decal is applied and when dry, the Softener is brushed over the top and left to dry for a couple of hours.
I followed the decal solution instructiions to get the first layer of decals applied. The fuselage and under wing roundels have seperate red circles. This is a pain, but the kit is old and that's how it could be done then.
After the decal softener for the first layer had dried, the rest of the decals were applied using the same method. Seems to work OK and the decals seem to have settled into the panel lines. Tamiya decals can be quite thick but with thinner decals this would have worked even better.
The decals need sealing with a little gloss varnish, then the model can be weathered.