Here's a vacuum diagram that looks to me
like what you have.I know that it sounds funny, but I'd keep the distributor vacuum setup like you have with the pipes going down to the CTO switch and the non-linear regulator. If I recall correctly, it's to improve drivability when the engine is cold and to add a little advance at idle so you have less hesitation starting out. Your distributor advance is set up to work with the advance the vacuum system gives and you may have some problems without it.
Also, that back bolt hole should NOT connect to the inside of the manifold.