It is extremely important to set the rear bow height to the proper settings. Your auto could have had many tops installed over the years. Each manufacturer has a bow height which is suitable for their product & may vary from ours. We have suggested installation guide marks on many patterns, as well as suggested or proven bow height suitable to install our products properly.

We offer "GENERIC installation" instructions, based on many years of personal trim installation experience. Each auto has a wide variety of problems, which might be encountered during installation. We recommend the GM Fisher body manual(s) as an excellent guide, with all factory specifications & parts lists. These manuals can be located on the Internet, swap meets, or local car clubs specializing in your model. 

We strongly urge the installation of these items be performed by PROFESSIONAL installation centers with the correct tools & experience to handle any conceivable problem which might arise.