I have an old Mark 1 that I disassembled and can't get it back together (You've heard this before ?). The mainspring housing was very hard to get out. After working with it a while I printed a manual from Ruger (Mark II) but after following all directions when I get it back together I can't draw the slide back more than 1/4" and the safety will not engage. I'm not doing something right and I don't have a clue. I have taken these guns apart before and am a long time shooter. Any help/suggestions would be appreciated. Danny