Wealthy buyers looking for an electric Aston Martin may not have to wait until the brand's new Rapide E performance car—at least not previous owners who may already have an old Aston Martin lying around.

The company has joined other European automakers in developing an electric drive system for its classic cars.

Aston Martin mounts its complete retrofit electric drivetrain in what it calls a "cassette" that fits under the hood of its classic cars and mounts onto the existing engine and transmission mounts. That makes the conversion easily reversible to avoid diminishing the cars' recently eye-watering values at collector-car auctions.

READ THIS: Aston Martin Rapide E details revealed beyond battery tech

A screen discreetly mounted in the cabin lets the driver keep tabs on things like the state of battery charge.

The company showed off its creation in a white, 1970 DB6 Mk Ii Volante.

Aston Martin said it is doing the conversion to "future proof" its classic cars in an era when many cities are setting restrictions on internal combustion machines and even targeting outright bans on driving them.

CHECK OUT: Aston Martin may be first with 800-volt charging

“We are very aware of the environmental and social pressures that threaten to restrict the use of classic cars in the years to come," said Aston Martin CEO Andy Palmer, who was head of the team that developed the Leaf when he worked for Nissan. "Our Second Century Plan not only encompasses our new and future models, but also protects our treasured heritage."

Aston says its electric-conversion cassette uses parts from the upcoming Rapide E, which is slated to use a 65-kilowatt-hour, 800-volt battery pack that will give it 200 miles of range and ultra-fast charging.

The Works Heritage EV conversion cassette may not be able to hold that much energy but may deliver the fast charging of the Rapide E.

DON'T MISS: Royal couple's electric Jaguar E-type Zero coupe will go into production

Owners who want the conversion will have to have it installed at the Aston Martin factory at Newport Pagnell, England.

The concept follows in the footsteps of Jaguar, which introduced an electric conversion of its classic E-Type this summer and decided to build the car after Prince Harry drove it from his wedding to Meghan Markle, now the Duchess of Sussex. The Jaguar, slightly smaller than the classic Aston Martins, holds a 45-kwh battery good for 170 miles.

Aston Martin did not specify the range, power, or price of its Works Heritage EV conversion. The company says it plans to start converting cars sometime in 2019.