I'm not familiar with the Omega D2 but looking at pictures on the internet it looks like a condensor enlarger, using a light bulb. So the easiest solution would be to replace original the ligt bulb with a regular household LED light bulb. Just make sure it is 4000K or higher. I use LED bulbs in all my enlargers and that works perfectly well. No need at all for complex / expensive modifications, Heiland modules or DIY solutions.