ances  of  the  same  item  will  have  the  letters “REF” in the applicable allowance column. To locate the referenced item locate the FSN or reference number in the index. The earliest figure and item number is the referenced item. Items authorized for use as required but not for initial stockage are identified with an asterisk in the allowance  column. (2) The quantitative allowances for DS/GS levels  of  maintenance  will  represent  initial  stock- age for 30-day period for the number of equip- ments  supported. (3)  To  determine  allowances  when  support- ing more than 100 of these equipments: First, di- vide the number of equipments supported by 100 by moving the decimal two places left; second, multiply the result by the quantity in the 51-100 density  column.  Example,  authorized  allowance for 51-100 equipments is 40; for 150 equipments multiply 40 by 1.50 or 60 parts required. h. One-Year Allowance Per 100 Equipments/ Contingency Planning Purposes.  Indicates  oppo- site  the  first  appearance  of  each  item  the  total quantity required for distribution and contingen- cy planning purposes. The range of items indi- cates total quantities of all authorized items re- quired to provide for adequate support of 100 equipments for one year. Subsequent appearances of the same item will have the letters “REF” in the allowance column. i. Illustration.  This column is divided as fol- lows : (1) Figure number.  Indicates the figure num- ber of the illustration in which the item is shown. (2) Item  number.  Indicates  the  callout  num- ber  used  to  reference  the  item  in  the  illustration. 4. Special Information a. Repair  parts  mortality  has  been  based  on 4000 hours operation per year. b. Parts  which  require  manufacture  or  as- sembly at a category higher than that authorized. for  installation  will  indicate  in  the  source  column the  higher  category. c. The  following  publications  pertain  to  the tank and pump unit and TM 5-4930-227-14 LO 5-4930-227-12 its   components: Operator, Organization- al,  Direct  and  General Support  Maintenance Manual Lubrication  Order d. The  same  illustrations  are  used  to  illustrate the repair parts and special tools listed in both organizational  maintenance  section  and  direct and  general  support  maintenance  section. 5. How to Locate Repair Parts a. When Federal stock number or reference number  is  unknown: (1) First. Using the table of contents deter- mine  the  assembly  group  within  which  the  repair part belongs. This is necessary since illustrations are prepared for assembly groups, and listings are divided into the same groups. (2) Second. Find  the  illustration  covering the assembly group to which the repair part be- longs. (3) Third. Identify the repair part on the il- lustration  and  note  the  illustration  figure  and item number of the repair part. (4) Fourth. Using the Repair Parts Listings, find the assembly group to which the repair part belongs and locate the illustration figure and item noted on the illustration. b. When Federal stock number or reference is known: (1) First.  Using the Index of Federal Stock Numbers  and  Reference  Numbers  find  the  perti- nent Federal stock number or reference num- ber.  This  index  is  in  ascending  FSN  sequence followed by a list of reference numbers in alpha- numeric  sequence,  cross-referenced  to  the  illus- tration figure number and item number. (2) Second. Using the Repair Parts Listing, find the assembly group of the repair part and the  illustration  figure  number  and  item  number referenced in the Index of Federal Stock Num- bers  and  Reference  Numbers. c.  When  the  Federal  stock  number  or  reference number is known and the repair part is not il- lustrated: (1) First.  Using the Index of Federal Stock Numbers  and  Reference  Numbers  find  the  perti- nent  Federal  stock  number  or  reference  number in  the  section  titled  Items  not  Illustrated  and note the group number. This section is in as- cending FSN sequence followed by a list of refer- ence numbers in alpha-numeric sequence, cross- -referenced  to  assembly  group  number. (2) Second.  Using the Table of Contents, lo- cate the assembly group number and page num- ber. vii