If any 200 six is changed to a Dual-Advance (swing-weights and vacuum) from a Load-o-matic (vacuum only), then MANIFOLD vacuum is used to the advance side of the vacuum chamber on the distributor. I highly recommend a SINGLE vacuum distributor because the vacuum chamber with 2 connections is for emission purposes only. Plug the connection closes to the cap if you have one. We don't need or want that. With the distributor set to about 10 degrees, which is 20 degrees at the crank (the limiter is inside the distributor under the points plate and it probably has 2 positions), and the static timing at about 14 to 16 degrees, that gives us 34 - 36 degrees total advance and we can run regular ethanol gas safely. I recommend 89 octane to be extra safe. I am 73 years old and spent decades building my own distributors from scratch (ASE certified engine builder). Mallory, ACCEL and others build good distributors but for street use they are usually an unnecessary extra expense. With top-of-the-line parts (I use BWD SELECT) we get brass/copper contacts (not aluminum) and the best over-the-counter stuff we can replace anywhere we travel. If you keep the 1100 carb, block off the ported vacuum and plug the spark-control valve. With manifold vacuum you have better idle and some advance once the engine rebuilds vacuum at speed. It then advances timing as you let-off the throttle or ease off when slowing down, giving a better burn. Just remember, the 1100 one barrel with a spark-control valve sends ported vacuum to the load-o-matic distributor, advancing timing as vacuum increases because the port is ABOVE the throttle plate. Manifold vacuum is tapped BELOW that plate so swing-weights advance timing as rpm increases, then vacuum advances as you slow down. It ain't as difficult as it sounds. Drag racing distributors (no vacuum chamber) work great at the track where they seldom see lots of idling, but on the street DUAL-ADVANCE is wanted. I rebuilt both race and street engines and they require different thinking where timing is concerned. Hope this helps.