Hello, can anyone here confirm the existence of Makkasan train station, supposedly very close to the Ratchaprarop ARL station, where one can pick up the Thai Railway trains running east toward Cambodia?  The only decent online reference I'm finding is at train36.com/makkasan-railway-station.html. If I can nail down the location of this station, I'd like to use it as an alternative to the main train station at Hua Lamphong. Thank you. 

Yes station exist-along the (former) giant repair works of the SRT. PLUS that train also stops at many, many, many more stops/stations/halts, incl ALL below the ARL on its utter long run to Aran. Just compete with the 1000s of free-loading Thai students as far as King Mongkut college. Do NOT even try to reach it from Makasan ARL-stop. And prepare yourself for slum-dwellers. I think its all on google maps-and you surely have that smartfone, nah?

It is located around 300-400m east of Ratchapraprop rd and ARL station, you can't miss it if you follow Nikkom Makkasan rd which runs along the railway line.