Your code is a complete train wreck so I'm not going to even try and guess where your head is at. Instead, working from your specification, I guess you want something like:

use strict;
use warnings;

while (defined (my $header = <DATA>)) {
    my @parts = split ' ', $header, 17;
    
    next if @parts < 12;
    processEvent ();
    print join (' ', @parts[3, 4, 6, 5, 7, 8, 11]), "\n";
}


sub processEvent {
    <DATA>;

    for (1 .. 8) {
        my $line = <DATA>;
        
        last if ! defined $line;
        
        my @parts = split ' ', $line;
        
        splice @parts, 3, (@parts - 3) if @parts > 3;
        s/[^\d\s.]+/ /g for @parts[1 .. $#parts];
        s/^\s+|\s+$//g for @parts;
        print join (' ', @parts), "\n";
    }
}


__DATA__
82  2 22 1043 54.7 48.020 114.037 17.5 3.2     2.9 13 177  84.3 0.20  
+1.6  2.7 C MBMG *         3.1 KALISPELL VALLEY; FELT            3.07
82022210
BUT EP4432.804ES60.7
LRM IPD4435.40 IS67.2  180.
AMM IPD4429.50 ES57.3  133.
MSO EPC4415.90 ES32.3
CMT EP4430.50 IS58.3
LDM IPC4412.20 ES24.3 3
RXF EPC4414.3
CLX IPC4408.70 ES19.7
[download]

which prints:

BUT 4432.804 60.7
LRM 4435.40 67.2
AMM 4429.50 57.3
MSO 4415.90 32.3
CMT 4430.50 58.3
LDM 4412.20 24.3
RXF 4414.3
CLX 4408.70 19.7
1043 54.7 114.037 48.020 17.5 3.2 177
[download]

Note that this code is not at all robust and depends on the event records' layout being consistent.

Thank you for all your help. I apologize for the confusing code. Thanks again.