||Hi I was lookin for a 57 gmc 4104 and came across this site. Im not real familiar with what your looking for but I'm a master tech with 30 years in the auto/truck industry.Ive seen buses for sale with intermittent reverse problems.
I guess what I'm wondering if you got straightened out?...is it a simple external mount solenoid?could a 2 bolt 4 wire ford starter solenoid be substituted?after all... a solenoid is a solenoid. I occasionally have to replace shift solenoids in newer Gm tranny's inside the unit. But back in 57 I imagine it to be simple circuitry....then again I never have seen what you need.Is this an RV you have?I was looking to possibly live in one of these busses. Just curious...and thanks ! Brian