Remember that aluminum corrodes, especially when in direct contact with steel. Find a pit or get it up on blocks and have a good look under there. My 4104 is so old that most of the high wear items (levelling valves etc) have already been replace/upgraded. The POs really influence how good the rig is. iwould get an IR gun (you'll need one eventually) and give the bus a good run and check hubs and difs etc...Tha's all I know except an old bus that has been completely rewired would be good, 40-50 year old fabric wrapped wire is a short waiting to happen.
