The 13" drums and shoes come in 2 different widths - 2.5" and 3.5" .
The 11 5/32" drums come in 2.75" shoes.
As for getting it off, a hammer and force seem to work good for me.
When you had your LP off, did you get a good flow of fuel out of the line? With an IP as fresh as yours is I would think it would be able to suck enough fuel to run at idle. I am thinking you may have a restriction somewhere.
Is his PMD still on the pump. My 95 has a hesitation and erratic throttle when cold. I heated up the PMD with the hair dryer and it went away. Waiting to get one relocated to confirm.