Some of these freeware airplanes are really at payware level.  The design and flight characteristics are truly exceptional and represent everything to the T.

However, sometimes the old adage "less is more" would make the airplane even better. This is especially true when it comes to gauges glare and windshield. Some of these gauges become unreadable in Sim. In real life, even after flying different types of airplanes in Floridian sun, I've never had a gauge become unreadable due to sunlight. Mostly because just about all pilots wear polarized sunglasses.
Windshield is another thing. I just dowloaded one of the most beautiful rendition of a Piper Apache. Unfortunately, the windshield is designed to looked grazed, dirty and old. It cuts the visibility so much that if it were a real plane, the A/P would fail the plane during annual inspection.
I recognize the time and talent that goes into creating these incredible sims, but please, please don't undermine your effort and time by going "overboard" on some of these details.
I hope none of you are offended by this as it's not the intent. I just don't want to see you waste your time of something that in real life is unrealistic...

There's an easy fix for the C150 glare problem. In each texture folder, there's a file called glass_CV.bmp - make a back-up before you start. Open one of these files in DXTBmp, and then double-click the alpha channel image so that it opens in your preferred graphics program. The RGB values for the windows in the default file are RGB all set at 136. Re-set these to 100 (in other words, darken the alpha to give an increase in the window's transparency), save, reload in DXTBmp and then save the file as DXT3 (the default). It's now much easier to see through the windows, and the internal reflections are still visible. You can vary the value to personal taste - mine's set at 100. Copy the file to the other folders, and all the textures have the new visibility glass.

The process is probably pretty much the same in the Piper Apache, but I don't have it (where did you get it from?) so can't identify the file.

Hope this helps.