Changing out steel screws in aluminum rails

Spent a good portion of a day changing out most of the steel screws in the aluminum rails on our 177.  Changed 174 screws with a #10 stainless screw that was 1" in length.  Also purchased a bag of 1.5" screws as I have read previous posts where owners found this length used here and there on their pods; in my case all were 1". 

Interesting in that the worst one were found on the underside rail near the tires, many had totally rusted out - only the head came off - new holes had to be drilled for the replacement s.s. screws.  What totally surprised me, as our 177 has been used for 10 seasons, is that the screws along the top as well as most in the slide out area appeared to be brand new in appearance, they were still shiny in the thread area.  I did not replace those (30 in the slide out and 12 along the top on both sides) as I figured if they haven't even begun to show any rusting after 10 years they probably won't after another 10.  Also replaced the 1" vinyl trim (white) as that was showing signs of wear and cracking.  A 100 foot roll took care of that.