IDEAS NASA Apollo Saturn V, Part 4 - Parts Bag #3

Work is progressing very well on the Saturn V model, with the completion of parts bag 3 which covers more of the first stage booster section.

I encountered a bit more difficulty in assembling the bracing/ locking parts at the top of the assembly.
Once the four sections of outer 'skin' are built, they must be attached to some SNOT assemblies at the top of the section.

Then a pair of 4x8 half-round plates are applied to lock the various parts together.

The trouble is that each plate must be lined up with 5 different SNOT assemblies around the perimeter as well as attaching to the central 4x4 round brick. 

All of the perimeter SNOT assemblies move around and are prone to detaching and falling off of the model while one is attempting to attach the plates.

It takes a bit of finagling to get everything lined up and in place.  Once those plates are finally on, the whole affair is quite strong and sturdy.

Here's the model, completed to this point...