Manual assembly in high variety - low volume production is challenging for the operators as there might be small changes from one product to the next. The operators receive adapted instruction sets to be aware of these small differences, currently either printed or presented on a computer terminal. Augmented Reality (AR) is considered the future of work instruction display as it promises hands-free interaction, but interacting with AR interfaces can be problematic in production environments.In this paper, we report on an exploratory study where we compare tablet interaction with three different ways of touch interaction for AR glasses: on the table, on the glasses, and the lower arm. While keeping the instructions the same in all conditions, we measured how placement affects the overall workload while performing an assembly task. Results indicate that combining additional wearable touch input with AR glasses is at least a promising direction for future research and, at best, an enabler for more widespread AR usage in manual assembly.