Hy RB55, to mount the 700R4 to the 261 will require an adapter, possibly a special flywheel and a starter, I believe there are kits available to do this. One factor in this swap that is often overlooked is the throttle pressure linkage for the transmission, the throttle pressure adjustment throughout the r.p.m. range is critical to the life of the transmission. I am not aware of a kit to operate the throttle pressure cable correctly for our inline six induction systems, but some research on your part may locate such a kit. Another factor is the current engine rear crossmember, it will have to be modified/lowered to allow the transmission clearance for installation, also a new crossmember to support the rear of the transmission may be required. I am assuming that you are going to convert to front disc brakes only, although the way it is written in your answer one could get the impression that you might be going the whole disc brake route. You will require the disc brake kit of course, you will also require a "combination valve" to separate the two systems and adjust the pressures to each system for the best braking balance. Most dual master cylinder kits available when converting to front disc brakes use Corvette master cylinders which are designed for full disc brakes, to use that type of master cylinder for a disc/drum setup you must use a 10 p.s.i. residual pressure valve in the rear brake system. Good luck with your project, hope that helps.
