I agree, all these modules accompany the regular incandescent lamphouse, which is shared. The VCCE module has the facility to bypass the filters if required (white light).
If you can work with the dichroic color module, which also has a white light facility included, and are looking to purchase one I have one that is like new, it was included in the package when I bought my 4550XLG, it is never going to get used, it will be a lot less than the price KHB shows, if you are interested please contact me via the forum, we may be able to agree a deal.
PS tables that give the dial settings of the color module that correspond to variable contrast filtration are published by Ilford on their website.