Niels van Roij Design late last year revealed the first details on a Ferrari Testarossa targa conversion the company was working on.

This week, the Dutch car customizer and coachbuilder provided an update, including the reveal of the new name for the project: Guida Touring Sport. It's no accident the initials are the same abbreviation that Ferrari often uses for its open-top models.

Ferrari never offered an open-top version of the Testarossa, though it produced the wedge-shaped V-12 supercar for more than a decade. A Testarossa Spider was built at one point, though this was strictly a one-off built for Gianni Agnelli, Fiat's chairman at the time.

This means significant modifications are required to not only ensure structural integrity is maintained, but also that performance hasn't diminished.

Ferrari Testarossa targa conversion at Niels van Roij Design

Ferrari Testarossa targa conversion at Niels van Roij Design

Key modifications will include strengthening of the door openings and the addition of new crossmember beams under the vehicle, Niels van Roij Design said. A diagonal piece will also be housed within the original center stack to further reinforce the chassis.

Reinforcements will also be added inside the A-pillars, which will be important in case of a rollover. Behind the dash, a pair of triangular sections, one on each side of the cabin, will connect the floor, side sills, A-pillars, and firewall to further enhance rigidity. Additional reinforcements will be added beneath the firewall.

Niels van Roij Design hasn't provided specifics on what it plans for the roof, though the company has said its design will stick with classic aesthetics.

It also isn't clear whether any upgrades are planned for the Testarossa's 4.9-liter V-12, though previous Ferrari conversions from Niels van Roij Design didn't feature changes under the hood. The donor car in this build is a 1987 example originally delivered in Europe, meaning it likely has around 380 hp. The mid-mounted engine is mated to a 5-speed manual and powers the rear wheels.