I have also found the church records you've mentioned for Melchior Biehl. I've also located him in the land records of Adams Co., PA and Frederick Co., MD. He was an executor of the will of Jorg Bittel/Bittle of York Co. (now Adams Co.) PA. and was mentioned in the will of Jacob Biel of Allegheny Co., PA. I believe that David Biehl (my g-g-g-g-g grandfather), Jacob Biehl and Melchior Biehl are brothers. There's also is the possibility of another brother Jonathan. David Biehl's daughter, Anna Maria Elizabeth, married George Michael Bittle, son of the afore mentioned Jorg Bittel. I've also located a German website that gives Catharina Alspach as the daughter of Johann Mathias and
?Anna Barbara Alspach. That she was born in Frogs (this is a translation done by the computer, so would need to be checked) ca. 1735 and established in Berks Co., PA. Also that she was a sister of Johann David who also established in Berks Co., PA. I have found no cemetery records for Melchior or David. David did die ca. 1810. I've also found the Biehl name spelled variously as Beel/Beal/Biel/Buhl/Buehl. Hope this has given you a few more possibilities for search.