Rob,
You are correct. The Beech Twin Bonanza 50 series was the only Beech model with factory option of JATO installation on the Approved Type Certificated models. All models from the very first Twin Bonanza were JATO-approved.
They were the Beech Model 50, the B50, the C50, the D50, the D50A, the D50B, the D50C, the D50E, the E50, the F50, the G50, the H50 and the J50.
The JATO bottles were installed in the aft section of the twin engine nacelles, one in each nacelle.
Beech built 883 Model 50 of all types, starting in 1950 through 1963. The first flight was November 11, 1949. It shared many parts with the single-engine Model 35 Bonanza. CAA certification was granted in May 1951. The design was marketed as a light twin engine step up from the single engine Bonanza sited below the heavier Beech Model D18S. All Twin Bonanzas used geared Lycoming engines; some later models were supercharged and some used fuel-injection with supercharging.
This total built does not include the Seminole military prototype models or military contract production of the Twin Bonanza for US Army aviation starting in 1951, which would bring the total of all to around 1,100 production.
Not part of quiz #15-these military models included the Model 50 (YL-23) L-23A prototypes, the B50 (U-8D/L23A) LH-9, a D50 that became L-23E, E50 (U-8D), E50 (RU-8D) and E50 (U-8G) builds.
The Twin Bonanza's popular nickname was the T-BONE, probably from military slang usage which was also used by civilian pilots. As all models had three front seats, all flight instruments were grouped in front of the pilot, with engine controls to left of center for middle passenger comfort.
There was at least one twin engine conversion of a Model 35 single engine V-tail Bonanza done in Oakland, CA by STC if memory serves. I believe that used a Baron wing on an early Bonanza fuselage. All Beech T-34 Mentor series single engine military trainer production also used a Baron wing.
Thank you for your rapid response.