The flat trim can also be purchased on the website under the "shop" tab, or you could try to find it from a local window contractor. We have step by step instructional videos for sale on the website at how-to-install-windows. Have your helper hold the window while you go inside. Next week we are going to start discussing sliding glass door replacement. All of the procedures on the inside will be exactly the same, from hole plugs, to insulation, to trim and caulk. Then you and a helper set the bottom of the vinyl window onto the old aluminum bottom track and raise it into China Parallel Twin Screw Barrels position. Do not use the foam insulation that comes in a can. To learn more, visit How To Install Windows. We sell the hole plugs on the website.First, you want to plug the 3/8" screw holes to hide the heads of the screws. This covers all the insulation and the old metal frame.com. Let's start with the retrofit frame. Again, I prefer the flat trim. Drive one screw in the bottom center, caulk around the screw head, then put the track back in place and re-install the sliding panel. The next step is to fill the gap around the new frame with R-13 Insulation. Prepare the window by drilling 3/8" holes in the areas of the frame where you want to screw it in place. Normally, there will be 3 holes on each side and 3 more across the top.John Rocco has been installing replacement windows since 1978.Once inside, you want to center the window in the opening. That's the flush fin that goes against the outside surface, usually stucco. To adjust for out of square conditions, shim the bottom right or left corner by placing a shimming material between the sill and bottom of the window frame. Don't predrill any holes in the bottom track. The plugs will pop into place in the hole. Pack the insulation in tight. This week I'm going to explain the installation techniques for both frame styles. You cut the top and bottom first, stick them on the vinyl frame, making sure the trim goes to the drywall. The final step is to caulk where the trim meets the walls. Slide the vent panel open and closed to make sure the window is plumb and level. But, there are a few differences. Once square, drive a 3" deck screw through the 3/8" holes and into the wood studs.