ok i assembled my ls motor ad everythign from the oil pan. to the cams. im working on the timing belt now. the cranks pulley is at tdc, (red white red mark its straight up) now when i put the cams in the marks wernt straight up. i try turning the but the valve springs wont let thestay. this is the only difficult part i am having. anyone have soe info or advice they could lend?

 

the cam caps nearest the timing belt has a hole for a 5mm punch to hold the cam at tdc

also tdc on the pully is the white mark furthest from the group of three
what i usually do is put a long as extention in #1 spark plug hole to visually make sure i have tdc

if your putting the timing belt on, there is a mark on the oil pump gear that points to an arrow on the oil pump