Couple of things. 1) the olds 260 is a tough motor. You can run it hot, frozen, low oil, itll take almost anything you throw at it. 2) chances are thats a t-200 tranny, not a t-350. Its possible, but I would make sure. 3) the Olds motor mounts from the other car are what you need. The holes are in place for the mounts, just bolt them in and go. Measure from the rear of the motor to where the mounts origionally were. The locate where the factory tranny ended. It wont put you dead on, but youll be in the ballpark. As for the Dog @ss motor, there are a few tricks to improve that engine. Bring up the timing a bit(2-4 Degrees) Rebuild or toss the Dualjet. I reccomend a Edelbrock replacement. Gap the plugs @ .30 or .40 . Also, down on the driver side there is a exhaust shutdown valve. More often than not, these dont work. Wire it open. It'll be a bit cold blooded, but youll get a lot more response. If you need anything else, just ask