Very newbie with bogging problems above half throttle. Followed all the suggestions about fuel system problems: Pulled and cleaned carbs, fuel switch, replaced gray fuel lines, cleaned tank, fresh gas, hi and lo speed adjusters etc. Some posts said problem could be rectifier. Checked with voltage meter. 12.4 before starting, 12.9 after starting. According to posts, voltage running should be 13.8-14.2. How do I get into the electrical box without pulling the gas tank? Help