The Q1 and 1 Rec are on the heat sink block. The Q1 kit includes the 1 Rec. More than likely you will receive an updated Q1 transistor with an additional red wire on it. I wouldn't replace the Power board unless you had traction motor field fault(code 29).
I would replace the Q1 and 1 Rec and double up on the heat sink insulator. Just verify you are over a 100k on your shorts to frame. This code is associated with the traction motor armature current. I'm assuming you already checked your brushes and commutator condition.
Code 23 usually is the Q1 transistor failed. I have had them fail on all the different Easi lifts (SA, SB, REACH, OPC). They sell the Q1 as kit because the 1 rec would take out the Q1 and technician's were only replacing the Q1 having the new Q1 fail. It is recommended to place both at the same time.