The Park Avenue is a big mix but a c body and an h are very similar.
There is alot of performance product that works on the Park Avenue and the car is sportier than the Le Sabre.
Some years the pillars will cross with the 92-99 Bonneville, so some years will have pillar pod options.
4t60-e bulletproof transmission.
if you are dealing with a series 1 3.8 then read up on DR jays build. Basically it will need a turbo or sc swap. Either will give you a big boost.
Park avenue = possible sleeper with style.
Oh if you really want to go wild a v8 will fit.