Converter should be accessible behind the WFCO distribution panel, breaker box and fuse box if you will ( called distribution panel because it distributes the 110v AC and 12v DC to the coach). Unplugged from shore power remove the screws holding the cover on. Remove the screws holding the distribution panel to the cabinet face stiles and gently pull the distribution panel out and set it on the floor in front of the opening. Should be 12+ inches of free wire to allow for access behind the distribution panel. Should be no need to empty your basement of stuff and remove part of a wall and crawl behind to reach the converter.
Are you thinking of changing it out to a different one? If you recently replaced batteries and accidentally reversed the battery terminals and blew the fuses it would be easier to get to the converter from the opening created by removing the distribution panel.
Chris & Maria
2012 36RL, Full Body Paint, Dual Awning, Dual a/c, Splendide Combo, Fisher Paykel dishwasher, 6.5kW Onan, Goodyear G614's. 2015 F550 6.7l, 4X4, Lariat, CC, 176" WB, Long Box, B&W Companion