Chevrolet Repair: valve job for caprice 1994, valve job, compression test

Question
when valve job for caprice 1994 shoud be done i have caprice
1994 i drove 270000 miles since i bought i run good but someone told me i have to do valve job now

second qs  fuiel pump has smale 2 holes covered with rubber do i have romeve when insall the pump

Answer
Do a compression test if all cyls are within 10% of each other and within 25% of the stated compression you are fine. do a wet and dry test that will tell you if any lower compression in any one cyl. is a valve or ring problem.lower dry= valve  higher wet = rings i do not understand the other question....are you asking about the lines on the sending unit itself or on the fuel pump