Many older Sohmer spinets have an external lyre and trapwork system, similar to that of a grand. The trapwork levers are rotating rods with flanged ends (like the damper rod on the action itself) which are mounted to the underside of the keybed. Usually the left and middle pedal rods connect to the same trapwork lever to activate the "soft" function; there is no "bass sustain." The keybed trapwork levers connect to the damper rod (sustain) and the hammer rest rail (soft) with short pitman dowels with pins on either end. All service on the lyre, pedals, and trapwork is performed externally. To remove the knee board to gain access to the drop action and strings, the lyre must be removed first. However in doing so, the trapwork levers rotate and drop down, and the pitman dowels fall out. To re-install the system, the trapwork and pitman dowels must be held in their proper positions while simultaneously mounting the lyre. This is very difficult without an assistant, and there is little space or access within the piano to install the pitmans after the lyre is screwed into position and the trapwork lever rods are fully rotated and supported. I have found that a solution to this problem is to take a long, thin screw (like a keyslip screw or dampp-chaser humidistat mounting screw) and insert it into the pedal rod hole in the trapwork lever flange. While holding the pitman and rod in position, screw the trapwork lever upward directly to the keybed. (The dampp-chaser screws make this particularly easy since their hex-heads can be held by a magnetic socket in your power driver, while holding the trapwork system with your other hand).