Need help with my G3-build

I got a set of the GPM as a part of a lot buy. Though I've never used them, I don't think I trust them. The alloy feels extremely cheap and they're not very thick anywhere. It looks dinky next to the plastic on the proline bellcranks.

Neil, are the 3905 GH bellcranks compatible with the gorilla/3906 style trucks? I wonder if I could get a set of those, use an old or modify/fabricate a centre link and continue using my lunsford turnbuckles?

.dk