my 95 was always hard starting in the am. thought is was natural, did some reading on TDR an found out that i might have a bad over-flow valve. went to cummins and they wanted over a $100 for it. bought mine off ebay for $30. put the new over flow valve in and WOW what a difference. ps when i took the old one out the insides were all broke. spring and check ball all came out in mutipple different busted pieces.
Fuel pressure test should show if it was working or not