Slant runs like crap when first accelerating..

You shouldn't have randomly moved the distributor hold-down plate relative to the distributor body. That adjustment is only for if you can't get enough movement in one direction or the other to attain the correct base timing, which is not the 0° you first read (and is also not whatever monster amount of timing advance you randomly cranked in by moving the dist plate). Verify that the timing mark on your crank pulley actually indicates TDC, then set the engine idle speed correctly, disconnect the vacuum advance and plug the carburetor port, then set your timing at 5° BTDC.

Tune-up parts and technique suggestions in this thread. Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download. The engine might also be overdue for a valve adjustment.