i started slotting some of the bellhousing screws back in the 70' when removing them it is much easier to slot them and run them out (and in )with screwdriver . that way you can skip removing the heater feed elbows. i mention it to some teacher at the gm training center over lunch then heard it was printed in a dealer post. i have seen it done a lot since then. speeds up clutch jobs. regards tim colson