[Enchilada]

Fairly simple to calculate, but it depends on the specific usage.
The difficulty is to convert Right Ascension into arcsec/arcmin, so as the position are in terms of the Declination (already in arcsec/arcmin).
Basically, the aim is to find the positions in x, y co-ordinates.

I've attached the method and examples to do this in a pdf

Hope this is useful...