A remap will not sort the problem. The problem needs to be diagnosed first then fixed, it may be something very simple, but best bet is to get this resolved. Once sorted, then think about getting it remapped. Might be worth driving it in it's current standard state of tune once it's fixed and then see what you think....
A few '63 owners have had remaps on here with good results, mainly via Eurocharged. If you do want it remapping soon then Acid (MSL) has organised a special tuning event where Jerry (owner of Eurocharged) is coming over to remap some cars. There may still be places left, but may be best to contact Acid. See thread here;
http://www.mbclub.co.uk/forums/amg-performance-lounge/150272-eurocharged-return-uk.html
Jules