7.4 gen v marine power PUSHRODS HELP/QUESTIONS

Hi All, Ran into this situation working on clients inboard 7.4 GEN V. He had exhaust leak and bent some valves and push rods. Heads/valves were reconditioned by local shop.Machinist said no material removed from head. Several intake and exhaust push rods purchased to replace the original ones that were bent. New ones are same size as the original ones that came from marine power. My first time seeing this engine all parts were there and ready for me to just reassemble. I installed the heads,all fine. Installed original flat tappet hydraulic lifters. Now comes the issues/questions. The push rods have a guide that has MARK V stamped. p/r aka pushrod. The p/r intake and exhaust have no adjustements,0 lash, just torque to 45lbsft. My questions are that when installed,valves closed,I still have 2-3 turned on the rocker stud before I can get any torque thus opening the valve. I know the lifters have oil in them still, but this seems like too much preload on the lifter. I went to my local shop and got sbi pushrods using block ID numbers,gen v and heads id numbers.Block and heads both are GEN V. The proper pushrods for this engine are couple mm shorter than the ones that came installed from marine power. Does this make sense? has anyone come across this? The engine ran fine for several years client said. Anyone know aprox lifter pre-load on this gen v 7.4L with "mark v" p/r guides. I am going to install the new shorter sbi p/r this weekend, so either way I'll see if my problems will be fixed. Option 2 get adjustable rocker stud with nut. If any engine guru can shed light on this issue I appraciate.
Thanks
Skipper

I don't think the machinist told you the whole story....he may not have "decked" the heads but he definitely removed some metal when the valve seats were resurfaced. This "raises" each valve, and with fixed rockers, means shorter pushrods.....to maintain the same lash. You can install the shorter pushrods or you can get aftermarket "old style" adjustable rockers....and I think the latter is usually "better" in that it gives more flexibility down the road (& usually saves a few coins, too).