After poking around inLXDE a bit, it was clear that the only problem was that PCC didn't have an option for /dev/ttyacm0.
Then I recalled that I already had a local repository on a removable hard drive (I'd bought cds from OSDisc.com when I bought PCLOS KDE) it hadn't occurred to me that I could use that in LXDE to get wvdial. It took some trial & error in a terminal with wvdial & wvdialconf but I'm now typing this in LXDE.
Thanks for the help,
In case someone else finds this & wants more details:
1-In a terminal, su to root
this will scan for your modem & return something like this at the end:
Found an USB modem on /dev/ttyACM0.
/etc/wvdial.conf<Warn>: Can't open '/etc/wvdial.conf' for reading: No such file or directory
/etc/wvdial.conf<Warn>: ...starting with blank configuration.
Modem configuration written to /etc/wvdial.conf.
ttyACM0<Info>: Speed 460800; init "ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=
3- From a root file manager, open /etc/wvdial.conf in a text editor, type in the isp phone #, your user name & password in the indicated areas, don't forget to remove the comment marks in front of each line.
4- from a terminal type wvdial & it should go through the steps to connect .