318 bogging at high rpm, but only in first gear?

The 8:1 CR, 120 psi cranking pressure, is why it wants a lot of timing at idle.

To get the optimum idle timing [ let us ay 25* ], you have a couple of choices:

- shorten the curve in the dist to about 11-13*. That will give 36-38* at WOT. The low comp ratio will want more timing. This much initial could be hard on the starter & starter with a higher HP rating might be needed. Another way to retain the stock starter if it cranks slow: put an on/off sw under the dash that grounds one of the dist pick up wires [ also a good theft deterrent ]; get engine cranking, & flick switch to remove the ground,

- use an adjustable vac adv unit, connected to manifold vacuum [ MVA]. Use the factory initial timing [ say 12* ] & add the difference to 25* [ 13* ] with the VA unit. You will have to fabricate a stop to limit the VA plunger travel. It is all part of tuning......
The Allen screw in the VA should be wound fully CW.