The 20mm, I am using Master's pieces.
Six pedestals stuck into a handy bit of blue tack, and the mouns assembled to the shield. I find that easier to do with the shields still on the fret.

Some North star Bridge gear painted ready for fitting to fairly basic corvette bridge.

shields mounted on the pedestals, the holes in the mounts are too small for the stubs on the pedastals, so a good gel superglue is advisable.

Bridge detail fitted, including a couple of ready use lockers for the 20mm.

one barrel frame folded and fitted, five more to go.

Have got almost half way round the 4" platform with the ready use clips, forgot to photo that.
More soon,
Si