One day I will set up a digital/analog switchover system, but too busy to look into it at the moment.
Additionally, 1/32 slot cars are commonly used in organized racing. This ratio is quite common, meaning there is a wide range of 1/32 scale slot cars, tracks, and sets available for your racing pleasure. Heaps of opportunities to use different makes of analog cars, also without the expense of the digital chipped cars. These popular slot cars are a 1:32 ratio of a full-sized vehicle, making them twice as large as HO (1/64) scale slot cars. I actually bought a cheap analog power base off ebay, and two cheap controllers on sale for a few bucks each at pendle slot racing and put my track to use without the digital lane changers. I kind of suspect you might be able to use a new CU with your old lane changers and the pitlane with a pitlane fuel adaptor swap out, but I am not 100% sure. In the meantime you could look at this thread, but be warned, it might be a bit confusing for a newcomer! I hope someone can provide you with some clarity on this.
But I gather that there are still limitations on the black box (such as fuel load and possibly the ability to connect to a PC) over the newer Control Unit. For my own curiosity I had a look at a few old threads, but since I wasn't around at the time they were published, the context is a little difficult to grasp on some of the posts.