After the shop assistant and I had our nap, it was time to fix the directionality of the file cuts with some 120 grit sandpaper on a block, and then work through 180, 240, 320, 400, 600, 800, and 1200 grip sandpaper smoothing things out.
It took a solid two hours to get out of the 180-240 stage on both guns. It seemed like every time I thought I was done, I'd find another scratch that was too deep for the grit I was working with and I'd have to go back.
The 240-320 transition took about 45 minutes, then 400 through 1200 only took roughly 20 minutes.
Using the diluted rust-encouraging solution worked so well on Project 10-3 Five Seven that I decided to run an experiment on these two guns. Instead of starting with a double application of full strength solution, I started with a single, light application of 25% solution. The working theory is that using the diluted solution from the start will result in less etching of the metal surfaces and produce a better shine...albeit with quite a bit more time invested for the rust/boil/card cycles.
The bathtub was filled with hot water, and both frames, both yokes, and Rustbucket's cylinder were hung up for a nice rustfull relaxation session in the closed-up bathroom while I had dinner and watched an old episode of Top Chef.
Two hours later, all the pieces were boiled in distilled water for 20 minutes and some quality time was spent with the carding wheel. The result was less than I expected but definitely a step in the right direction. The full-strength method always puts a strong coat of blue down with the first rust....this time everything turned a very light greyish blue. I think I would call it a "shiny patina". The "shiny" part is what I was looking for.
Based on the results of the first cycle, I'm going to estimate that it will take about two weeks to complete everything at a rate of of one cycle per day after work. For now, all the pieces are untreated and hanging in the high-humidity bathroom until tomorrow so that some natural oxidation can help things along.
Stay tuned...this may be a long one.
You haven't met the other 3 yet. We'll come back to Rustbucket after I get some other things cleared out of the way...my short term plan is to clean up the insides, get her back together in a semi-finished state, and take her to the range so that she can tell me what else she needs besides new clothes. 
