I am building my first stroker and it is a 454 to a 496 I am using an eagle stroker kit with a 4.25 stroke crank and rods with srp forged pistions and was wondering about what I am going to run into on the clearance part of it where and how much is needed any help would be greatly apreacated thanks  

It shouldn't be too much of a problem but every block is different...

A lot of 'stroker' motors may need a couple of mock-ups. The factory notching at the buttom of the bores may not be sufficient and also some more notching may need to be done around the buttom of the bores before the oil pain rail. Also remember that you may need a notched oil pan designed for the added stroke. It's highly unlikely that you will need to grind on the pan rails, which is a good thing because a oil gallery runs through them.