Only Alex Albon has the updates this weekend, with Logan Sargeant having to wait at least until the next race in Austria before getting to run them.
The list of parts that have been changed includes the floor body, sidepod and engine cover bodywork. But there is also a revised mirror layout, a new halo fairing, new external geometry for the suspension fairings, rear brake ducts and rear wing endplates.
All of these have been fettled in unison in order that the various flow structures that are created by each surface can interact more effectively.
Given the scale of the changes, this is obviously not the work of a moment, as explained by head of vehicle performance Dave Robson:
"To get through the whole wind tunnel, aero development, design and manufacturing, it's a few months," he explained when asked by Motorsport.com about the timescale of coming up with the revisions.
"Obviously, it's been a little bit tricky getting it through manufacturing, following the various repairs we've had to do since probably Melbourne".
Production issues aside, the big-ticket items from this list, especially from a visual perspective, are the sidepods and engine cover.
Williams has pursued a deeper water slide-style upper surface geometry than the previous bodywork, whilst the hunched shoulder that used to feature on the ramp section has also been smoothed out.
Meanwhile, the shape and position of the upper cooling cannon outlet have been altered in order to perform better from both an aerodynamic and cooling perspective.
In terms of the floor, most of the finest details are buried away underneath, out of sight, as the team confirmed it has added some complexity in this area.
But, given the timescale between the now infamous reveals of the Mercedes, Red Bull and Ferrari as they were hoisted into the sky in Monaco, there's no chance that Williams has had time to work on any of those images and replicate what it has seen in recent days.
"There's nothing on there that's based on the other cars we've seen on cranes over the last couple of weeks," explained Robson. "It's a bit different. But it doesn't look like the Red Bull, I can promise you that."
To take advantage of the bodywork changes and the minor alterations made to the mirrors and halo, which also help correct the airflow's passage, there are a number of changes downstream too.
Robson added: "All of the rear suspension legs are re-orientated again to go with that revised flow structure.
"And the brake duct winglets are all updated again for the same reason. But they're really all just there to drive that flow into the rear corner and then the diffuser".
The lower section of the rear wing endplate has also been modified in order that it and the swage added to it a few races ago perform as anticipated, with the suspension fairings and brake duct winglets alongside it.
