I looked the Monteverdi wiki page and it doesn't look like any 340 cars.
They ran big blocks in 375 series cars.
The SUV Sierra model came with: 318, IH 345, or 440.
The Volare based cars were 318's.
There was one 'factory' built Dodge Dart 4 door coming out of the Swiss AMAG assembly plant in Schinznach (High quality Swiss made A - Bodies).
The story behind this unique car is strange - in Schinznach the cars were transported on car carriers between the different production sites and one day - as far I know in 1969 - a nearly finished 340 Barracuda fell from the carrier. The car was completely damaged - but the drivetrain was still ok.
In Schinznach were mostly 4 door Valiants and 4 door Darts built, and they used this 340/727 drivetrain for a 4 door Dart. This unique Dart runs in the 70s as taxi cab in Zürich and was well known...