I studied the threads and although great stuff........ can't find the answer to my question so please help ..... I have the '04 LB7. Is the "lift-pump" standard....do I have one or is it added an "after market" item? If "after market", is there one commonly recommended? Also....has anyone determined "for sure" the micron rating of the OEM filter .........and the filtration micron level of the after market add on pre-filters? Which after market filter is commonly recommended? thanks for any education you can give.