From fading memory (a risky proposition) if the motorhome has an oxygen sensor in the exhaust, it must have an ECM to drive the carb's mixture control solenoid. It should also have electronic sensors for other things, like manifold pressure, etc. I don't think these were used on units without catalytic converters.
2000 Holiday Rambler Endeavor 40PBD
Freightliner XC, CAT 3126B