Made a new interchange in SimCity 4 that could be built at the 401/VMP junction:
Inspired by this design:
The 401 would be the route at the bottom so it doesn't have to split up directions of travel.
That or a previously discussed clover-stack are good ideas for a free-flowing junction at VMP-401. The planned conversion to a parclo for a northern extension is stupid and delays converting the VMP to a freeway for decades.