There are always clearance challenges when doing an engine swap. One of these is routing the transmission cooler lines off the side of the transmission while cleaning the trans tunnel. Earl's makes this easier with their line adapters. Integrating into the GM transmission and adapting to AN lines allows additional clearance and freedom that the original hard lines cannot. Adapters are available for the popular GM Transmissions 4L80E (Fits Transmissions w/ 9/16-18 Threads Long/Rear). Order Two adapters (one short for the front and one long for the rear to match the threads on your transmission). The thread size varies depending on the application.