Mark,
I grabbed this from the VHPA website. it has the crash grid coordinates to 6 digits so that is plus or minus 100 meters.

Name: WO1 Martin Gehring Given
Status: Killed In Action from an incident on 11/21/1968 while performing the duty of Aircraft Commander.
Age at death: 20.5
Date of Birth: 06/02/1948
Home City: Northfield, MA
Service: AV branch of the reserve component of the U.S. Army.
Unit: 119 AHC, 52 CAB
Major organization: 1st Aviation Brigade
Flight class: 68-505/68-3
Service: AV branch of the U.S. Army.
The Wall location: 38W-026
Short Summary: With WO1 Robert Lee Storey. Nickname - Highpockets.
Aircraft: UH-1D tail number 66-16297
Service number: W3160763
Country: South Vietnam
MOS: 062B = Helicopter Pilot, Utility and Light Cargo Single Rotor
Primary cause: Hostile Fire
Major attributing cause: aircraft connected not at sea
Compliment cause: fire or burns
Vehicle involved: helicopter
Position in vehicle: aircraft commander
Started Tour: 07/01/1968
"Official" listing: helicopter air casualty - other aircrew
Location: Kontum Province II Corps.
Reason: aircraft lost or crashed
Casualty type: Hostile - killed
single male U.S. citizen
Race: Caucasian
Religion: Protestant - no denominational preference
The following information secondary, but may help in explaining this incident.
Category of casualty as defined by the Army: battle dead Category of personnel: active duty Army Military class: warrant officer
This record was last updated on 05/25/1998

Aircraft info
Information on U.S. Army helicopter UH-1D tail number 66-16297
The Army purchased this helicopter 0467
Total flight hours at this point: 00000543
Date: 11/21/1968
Incident number: 68112111.KIA
Unit: 119 AHC
South Vietnam
UTM grid coordinates: YA646508
Original source(s) and document(s) from which the incident was created or updated: Defense Intelligence Agency Helicopter Loss database. Also: OPERA (Operations Report. )
Loss to Inventory

Crew Members:
AC WO1 GIVEN MARTIN GEHRING KIA
P WO1 STOREY ROBERT LEE KIA
CE SP5 ONTIS BILLIE JOE KIA
G SP4 SUMPTER EDDY GALE KIA

Passengers and/or other participants:
SP4 HAUGEN WARREN GEORGE JR, AR, PX, KIA
SGT REIN CHARLES FREDERICK, AR, PX, KIA