Installing 58-182 window bubble seal

You should be able to just slide it in. Check the corners of the frame, that is usually where the opening to the groove is. If there is no such opening, check to see if your sash frame is screwed together. If so, you could loosen the corner to slide the 58-182 into the groove. If you have a welded sash, you could try to cut off a little of the leg in the corner so that you can slide in the weather strip.