Where did you get the vacu-form? I remember having one that made Hot Wheels style cars back in the 60s.
I bought it on ebay a few years ago . I think this is only the 3rd or 4th time I've made a part with it but it is nice to have . I also had one as a kid when they were new (1963 maybe?) and remember having tons of fun with it !
I spray all my old decals with Testors Decal Bonder before applying them only because I've been using it for years and it has always worked for me . Microscale also makes a brushable sealer and some people just spray them with clear .