I just found this blog, and have enjoyed reading the posts. I recently "fell into" a pair of SPP's. They are both missing the top covers, and one is missing the recoil spring and the plastic pin. I have been in contact with the people selling the BT guns, but they keep telling me "maybe next year". Besides, whats your opinion about putting the new top cover with the pic rail on the older guns. Waste of money? Thanks