I'm
sure you're familiar with abs and its installation. I'd just cut the old
drain at a convenient spot, and install a new trap.

Oh yeah...and I will. It's just a PITA job that'll probly end requiring
me to replace a piece I hadn't planned to replace 'cuz I'll probl'ly
crack it getting the parts I wanted to replace off.

I just replaced a p trap in the old side of the house upstairs bathroom a
few months ago ... I cut the old drain (vertical section near the floor) and
installed the p trap ... compression fit to the basin tailpiece, length of
abs
from the trap to the connector, and connector to the old abs drain. Took
less than an hour ... I'm the type that (usually) measures 4 times, cuts
once, assembles and checks the fit 1 once, and installs once ... and the
cost was maybe $5 or so ... but since I'm in the refurbish mode with my
current house (geez ... will I ever "settle down"), I had a few parts in the
"plumbing box", so all I needed to go get was the trap.