Here's a great film featuring the Scammell Pioneer. It's a Military Training film designed to give the REME recruits an idea of the capability of the British Army's 6 Wheel Heavy Breakdown Tractor. The film was produced in 1942.
Did my apprenticeship with a Ford main dealer 1970 to 75, we had a Scammell Pioneer as our heavy recovery truck, a Themes Trader as a light recover truck and a Landrover and trailer for cars, remember the scammell was great at its job did everything ever asked of it, I left the firm in 1978, and it was still in use then