[PROJ] Conversion from Tanzanian ARC1960 to WGS84

[Jean Louis]

Hello,

I would like to get possibility to convert
programmatically from ARC1960 how it is used in
Tanzania, to WGS84.

I did read this file:
http://lists.maptools.org/pipermail/proj/2009-August/004849.html

and this thread:
https://github.com/OSGeo/proj.4/issues/1110

And I am still not getting right result.

I have got the coordinate -1.47927 34.56933 from
GEOTRANS software. And I have compared it to the
Tanzanian mining cadastre, it is apparently the
same. 

However, I am not achieving with the below
conversion to obtain accurate coordinate.

Please help me if you can, so that I find permanet
solution, as it affects very many people who live
in Tanzania.

<gie>

operation	+proj=molodensky +ellps=clrk80 +da=-112.145 +df=-0.54750714e-4 +dx=-175 +dy=-23 +dz=-303
tolerance	2 m

accept		-1.47666 34.56861
expect		-1.47927 34.56933

</gie>


Jean