y/, \n/ /s

##</code><code>##

#!/usr/bin/env perl -l

use strict;
use warnings;

my @data = (
    q{"TRAY,HINGED,PLSTC,20 CAV 
    #F32473"},
    q{"BOX HSC,35-3/4X17-1/4 X 50-1/2
    SIMULATOR TALL BOX"},
    q{"PAD, FOAM, 24 X 24 X 1/4                #16193                                   
    112 SHEETS PER ROLL, ORDER IN FULL ROLLS"},
    q{"PKG LIST,ASST ARM,RAD,300
    #F37784"},
    q{"PAD, TOP CAP RE17-30048          #F30121                                      
    CORRUGATED ASSEMBLY, 22-7/8 X 21-1/8 X 4-3/4"}
);

print 'Before:';
print for @data;

print 'After:';
for (@data) {
    y/, \n/ /s;
    print;
}

##</code><code>##

Before:
"TRAY,HINGED,PLSTC,20 CAV 
    #F32473"
"BOX HSC,35-3/4X17-1/4 X 50-1/2
    SIMULATOR TALL BOX"
"PAD, FOAM, 24 X 24 X 1/4                #16193                                   
    112 SHEETS PER ROLL, ORDER IN FULL ROLLS"
"PKG LIST,ASST ARM,RAD,300
    #F37784"
"PAD, TOP CAP RE17-30048          #F30121                                      
    CORRUGATED ASSEMBLY, 22-7/8 X 21-1/8 X 4-3/4"
After:
"TRAY HINGED PLSTC 20 CAV #F32473"
"BOX HSC 35-3/4X17-1/4 X 50-1/2 SIMULATOR TALL BOX"
"PAD FOAM 24 X 24 X 1/4 #16193 112 SHEETS PER ROLL ORDER IN FULL ROLLS"
"PKG LIST ASST ARM RAD 300 #F37784"
"PAD TOP CAP RE17-30048 #F30121 CORRUGATED ASSEMBLY 22-7/8 X 21-1/8 X 4-3/4"