Auburn serial and identification numbers

With the exception of the engine number tag on the block my present Auburn came to me without the benefit of the usual ID tags. My previous auburns had numbers stamped on the frame, on the passenger side, which, as I recall correlated to the serial number[or numbers] on the tag and car number on the engine block plate. My title has engine number GU52333, but no car number. As the engine block number has no car number I am inclined to think that this is perhaps a replacement engine. So far I have not been able to locate the usual numbers on the frame, which should be on the right side frame rail towards the lower part of the frame. I am "re bodying" this Auburn and would like to have some numbers that are reasonably historically accurate. My title has no other numbers, other than the engine number. I would also like to have all my numbers just in case some staff member at the motor vehicle department decides to become difficult. Does anyone out there have any suggestions or data which could help me resolve this issue?