Today I installed the power antenna from a '92 Park Ave into my '92 LeSabre.
Yes, they're different power antenna units, but it was pretty much a bolt-in swap -
I had to use the exterior grommet & chrome retainer from the Park Ave'* antenna,
and install the shorter support bracket from my LeSabre'* old antenna unit onto the Park Ave'* unit.
Other than that, it'* a simple & inexpensive bolt-in replacement/repair
if you happen to have a LeSabre with a broken power antenna but only Park Aves in the local salvage yard..

Thanks for posting the info!