i dont think any of us have seen one on a series 1, so we cant give you a definite answer either way.
i know it will need to be welded in like on my 96 b/c we dont have a bracket to conect the dp to the cat.
what you may want to do, is look up the part # for the 95 and 96+ riv downpipe and see if they match. that would tell you for sure if the zzp will work.
1996 with 254k miles, L32 4" FWI -> ported N* -> Ported Gen V w/3.0" Pulley, Stage 3 Phenolic I/C, ZZP FMHE, 1.84 RR, Headers and 3" pipe to mufflers, F-body brakes, and lowered on Eibachs. -RIP
AMG C400 White on black -daily