Cajun Gun Works can mill a beavertail into the front of the slide and install pretty much any kind of front sight you need. Depending on the width of your rear sight dovetail they can also do some milling to install a fixed or adjustable on the rear. The older Pre-B's have a .348 rear dovetail so your choices get kind of narrow but if it's a later version it would have the more modern dovetail cut of .384, with a slight modification most any of the newer rear sights can be installed.
The single action only mod makes for a seemingly better pull and reset in most instances and also sets the trigger back for a much easier reach. With some work you can make any 1911 blush by going to the SAO with the addition of a few additional parts. The ones i have done this to for myself just seem to have to wiggle to fire and reset. I love the flat face of the trigger and the easier trigger reach.
Thanks, I appreciate the explanation.
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