Additionally, an independent piano restoration and tuning business operated above the workshop floor and studios for at least two years.

[2] The Guitar and Lute Workshop was started by Donald C. Marienthal, George Gilmore, and Keola Beamer in 1970 and was based in a warehouse building on Waimanu Street near Ala Moana Shopping Center.

In addition to guitars, specialty instruments produced at the GLW included lute, vihuela, and viola da gamba.

Gilmore learned lutherie in Spain (classic guitar construction) and influenced some of the techniques still used today at the Kamaka factory.

[10] A close friend of Gilmore, Ralph Hedges, established a piano tuning and restoration business adjacent to George's office and studio, and next to the workshop floor.