have to pull the advance plate out of the dist which means you petty much have to pull the entire thing apart. then its just a matter of closing up th eholes to whatever advance you want.
getting the correct plate? don't know if anyone sells them to tell you the truth. you can call FBO and he will build ya an entire dist. but that will be about $170 and your stuck with that advance. would have to send it back to get adjusted if you change your combo.
you can get something like a msd dist. which is easy to adjust everything. has bushings to limit the total advance and its easy to get to the the springs to change the speed of the advance.